anything that has mass and occupies space

the smallest particle of an element

the smallest particles on earth

name the three states of matter:

protons, neutrons, and electrons

metals, non-metals, and metalloids

freezing, melting, and evaporation

The Ultimate Chemistry Exams Prep Test

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1/65 Questions

Convert 20g to kg.
- 2000kg
- 20000kg
- 0.20kg
- 0.020kg

About This Quiz

In chemistry classes, we get to discuss a lot about liquid and how to form a solution. With the midterms just around the corner, it is becoming more critical to ensure that you are up to date with all covered in class so far. Below is a The Ultimate Chemistry Exams Prep Test designed to refresh your memory. Give it See morea shot!

The Ultimate Chemistry Exams Prep Test - Quiz

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2.

Convert 23ml to liters.
- 0.023L
- 230L
- 230000L
- 23000L
Correct Answer

A. 0.023L

Explanation

To convert milliliters to liters, you divide the volume in milliliters by 1000. In this case, 23 milliliters divided by 1000 equals 0.023 liters. Therefore, the correct answer is 0.023L.

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5
3.

Convert 18km to mm.
- 18000mm
- 0.0018mm
- 18000000mm
- 1.80mm
Correct Answer

A. 18000000mm

Explanation

To convert kilometers to millimeters, you need to multiply the given value by 1000 because there are 1000 millimeters in one kilometer. Therefore, 18 kilometers would be equal to 18,000 millimeters. However, the given answer is 18,000,000 millimeters, which is incorrect.

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4.

Convert 88kg to mg.
- 8.8mg
- 88000mg
- 0.0000088mg
- 88000000mg
Correct Answer

A. 88000000mg

Explanation

To convert kilograms to milligrams, we need to multiply the given value by 1,000,000 since there are 1,000,000 milligrams in a kilogram. Therefore, 88kg is equal to 88,000,000mg. The correct answer is 88000000mg.

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2
5.

Convert 23.6cm to mm.
- 2.36mm
- 236mm
- 0.236mm
- 0.0236mm
Correct Answer

A. 236mm

Explanation

To convert centimeters to millimeters, we need to multiply the given value by 10. In this case, 23.6cm multiplied by 10 equals 236mm. Therefore, the correct answer is 236mm.

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1
6.

Define matter:
- The smallest particle of an element
- The smallest particles on earth
- Anything that has mass and occupies space
- A positively charge particle
Correct Answer

A. Anything that has mass and occupies space

Explanation

The correct answer is "anything that has mass and occupies space." This definition accurately describes matter, which refers to any physical substance that exists in the universe. Matter can be in the form of solids, liquids, or gases, and it is composed of atoms and molecules. This definition encompasses all types of matter, from the smallest particles to large objects, emphasizing the fundamental characteristic of having mass and taking up space.

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7.

Name the three states of matter:
- Protons, neutrons, and electrons
- Metals, non-metals, and metalloids
- Solid, liqui, and gas
- Freezing, melting, and evaporation
Correct Answer

A. Solid, liqui, and gas

Explanation

The three states of matter are solid, liquid, and gas. These states are determined by the arrangement and movement of particles. In a solid, particles are tightly packed and vibrate in place. Liquids have particles that are close together but can move past one another. Gases have particles that are spread out and move freely. Protons, neutrons, and electrons are subatomic particles and not states of matter. Metals, non-metals, and metalloids are classifications of elements. Freezing, melting, and evaporation are physical processes that can occur within the states of matter.

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2
8.

What instruments do we use to measure volume?
- Thermometer
- Graduated cylinder
- Scale
- Ruler
Correct Answer

A. Graduated cylinder

Explanation

A graduated cylinder is used to measure volume. It is a cylindrical container with markings on the side that indicate different units of volume. By pouring a liquid or substance into the graduated cylinder and reading the measurement at the bottom of the meniscus, we can determine the volume accurately. Thermometers measure temperature, scales measure weight, and rulers measure length, but none of these instruments are specifically designed for measuring volume.

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1
9.

What instruments do we use to measure the mass:
- Graduated cylinder
- Thermometer
- Beaker
- Scale
Correct Answer

A. Scale

Explanation

A scale is used to measure the mass of an object. It is a device that uses the force of gravity to determine the weight of an object, which is directly proportional to its mass. By placing an object on a scale, the reading displayed on the scale provides an accurate measurement of its mass. Graduated cylinders, thermometers, and beakers are not used to measure mass, but rather to measure volume and temperature.

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1
10.

What instruments do we use to measure density?
- Scale and thermometer
- Scale and stop watch
- Graduated cylinder and ruler
- Graduated cylinder and scale
Correct Answer

A. Graduated cylinder and scale

Explanation

Density is defined as the mass of an object divided by its volume. To measure density, we need to measure the mass and volume of the object. A graduated cylinder is used to measure the volume of liquids, while a scale is used to measure the mass of an object. Therefore, the correct instruments to measure density are a graduated cylinder and a scale.

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1
11.

What SI unit is used to measure volume
- Grams
- Kilometer
- Liters
- Degree celcius
Correct Answer

A. Liters

Explanation

Liters is the correct answer because it is the SI unit used to measure volume. Volume is a measure of the amount of space occupied by an object or substance, and liters are commonly used to express the volume of liquids and gases. The other options, grams, kilometers, and degrees Celsius, are not units of volume but rather units of mass, distance, and temperature respectively.

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12.

Properties that cannot be observed with the five senses are called:
- Sub-microscopic properties
- Macroscopic properties
- Physical properties
- Biological properties
Correct Answer

A. Sub-microscopic properties

Explanation

Sub-microscopic properties refer to properties that cannot be observed with the five senses. These properties are too small or too subtle to be detected without the use of specialized tools or techniques. They exist at a level that is beyond the capabilities of our senses to perceive. Examples of sub-microscopic properties include the arrangement and behavior of atoms and molecules, as well as various subatomic particles.

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2
13.

A substance consisting of two elements chemically combined is known as:
- Mixture
- Solution
- Element
- Compound
Correct Answer

A. Compound

Explanation

A compound is a substance that is made up of two or more elements chemically combined. In a compound, the elements are bonded together in a specific ratio and cannot be separated by physical means. This is different from a mixture, where the components are not chemically combined and can be separated by physical means. Therefore, the correct answer is compound.

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1
14.

A mixture that separate into two visible phases is known as:
- Solution
- Heterogeneous mixture
- Homogeousmixture
- Compound
Correct Answer

A. Heterogeneous mixture

Explanation

A heterogeneous mixture refers to a combination of substances that are not evenly distributed throughout the mixture. In this case, a mixture that separates into two visible phases indicates that there are distinct regions within the mixture with different compositions. This suggests that the substances in the mixture do not mix uniformly, making it a heterogeneous mixture.

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2
15.

A positive charge particle found in the nucleus is called:
- Neutron
- Proton
- Electron
- Atom
Correct Answer

A. Proton

Explanation

A positive charge particle found in the nucleus is called a proton. Protons are one of the fundamental particles that make up an atom. They have a positive charge and are located in the nucleus along with neutrons, which have no charge. Electrons, on the other hand, have a negative charge and orbit around the nucleus. Therefore, the correct answer is proton.

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1
16.

A change from liquid to solid is called:
- Melting
- Boiling
- Freezing
- Condensation
Correct Answer

A. Freezing

Explanation

When a substance changes from a liquid state to a solid state, it is called freezing. This process occurs when the substance loses heat and its molecules slow down, coming closer together and forming a solid structure. Freezing is the opposite of melting, which is the change from a solid to a liquid state. Boiling refers to the change from a liquid to a gas, and condensation is the change from a gas to a liquid.

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17.

A change from liquid to gas is known as:
- Condensation
- Melting
- Sublimation
- Evaporation
Correct Answer

A. Evaporation

Explanation

Evaporation refers to the process in which a liquid changes into a gas state. This occurs when the molecules in the liquid gain enough energy to overcome the forces of attraction between them and escape into the atmosphere. Unlike condensation, which is the opposite process of gas turning into a liquid, evaporation specifically refers to the change from a liquid to a gas. Melting refers to the change from a solid to a liquid, while sublimation is the direct transition from a solid to a gas without passing through the liquid state.

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1
18.

A change from gas to liquid is called:
- Sublimation
- Evaporation
- Freezing
- Condensation
Correct Answer

A. Condensation

Explanation

Condensation is the process in which a gas changes into a liquid state. This occurs when the temperature of the gas decreases, causing the gas particles to slow down and come closer together. As a result, the gas particles lose energy and form bonds, forming a liquid. This is different from evaporation, which is the process of a liquid changing into a gas. Therefore, condensation is the correct answer as it accurately describes the change from gas to liquid.

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19.

A mixture of sand and iron particles can be separated by:
- Distillation
- Magnetism
- Decantation
- Filtration
Correct Answer

A. Magnetism

Explanation

A mixture of sand and iron particles can be separated by magnetism because iron is a magnetic material whereas sand is not. When a magnet is brought close to the mixture, the iron particles will be attracted to the magnet and can be easily separated from the sand. This method takes advantage of the difference in magnetic properties between the two substances, allowing for an efficient separation.

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20.

A mixture of salt and water can be separated by:
- condensation
- Filtration
- Crystalization
- Distillation
Correct Answer

A. Crystalization

Explanation

Crystallization is the process of separating a mixture by allowing a solvent (in this case, water) to evaporate, leaving behind the dissolved solute (salt) in the form of crystals. This method takes advantage of the different solubilities of the components in the mixture. As the water evaporates, the solute becomes less soluble and starts to form solid crystals. These crystals can then be separated from the remaining liquid, resulting in the separation of salt from water.

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2
21.

A mixture of sand and water can be separated by:
- Filtration
- Evaporation
- Distillation
- Crystalization
Correct Answer

A. Filtration

Explanation

Filtration is the process of separating solid particles from a liquid or gas by passing it through a porous material. In the given scenario, a mixture of sand and water can be separated by filtration because the sand particles are larger and will be trapped by the filter, while the water will pass through. This method is effective in removing solid impurities from a liquid, making it the correct answer in this case.

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2
22.

A mixture of peroxide and water can be separated by:
- Evaporation
- Sublimation
- Decantation
- Distillation
Correct Answer

A. Distillation

Explanation

Distillation is the process of separating a mixture by heating it and then collecting the vapor that is produced. In this case, a mixture of peroxide and water can be separated by distillation because they have different boiling points. Water has a boiling point of 100 degrees Celsius, while peroxide has a boiling point of around 150 degrees Celsius. By heating the mixture, the water will vaporize first, leaving behind the peroxide. The vapor can then be collected and condensed back into liquid form, resulting in the separation of the two substances.

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0
23.

Burning wood is an example of:
- Physical change
- Chemical change
Correct Answer

A. Chemical change

Explanation

Burning wood is an example of a chemical change because it involves a chemical reaction. When wood burns, it undergoes a process called combustion, where it reacts with oxygen in the air to produce heat, light, and new substances like carbon dioxide and water vapor. This change is irreversible, as the wood is transformed into different compounds with distinct properties. Therefore, burning wood is not just a change in physical state or appearance, but a fundamental alteration in its chemical composition, making it a chemical change.

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24.

Baking cake is classified as:
- Physical change
- Chemical change
Correct Answer

A. Chemical change

Explanation

Baking a cake is classified as a chemical change because it involves a series of chemical reactions. When the cake batter is exposed to heat in the oven, the ingredients undergo chemical reactions such as the breakdown of proteins, the caramelization of sugars, and the Maillard reaction. These reactions result in the formation of new substances with different chemical properties, such as the formation of a crust, the rise of the cake, and the development of its flavor and texture. Therefore, baking a cake involves a chemical transformation of the ingredients, making it a chemical change.

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25.

Melting candle wax is classified as:
- Physical change
- Chemical change
Correct Answer

A. Physical change

Explanation

Melting candle wax is classified as a physical change because it does not involve a change in the chemical composition of the wax. When the wax is heated, it undergoes a phase change from a solid to a liquid. The molecules in the wax rearrange themselves, but the chemical bonds between them remain intact. Therefore, no new substances are formed, and the properties of the wax, such as its melting point and density, remain the same.

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26.

Dissolving salt in water is classified as:
- Physical change
- Chemical change
Correct Answer

A. Physical change

Explanation

When salt is dissolved in water, it undergoes a physical change. This is because the chemical composition of salt (sodium chloride) remains the same before and after dissolving in water. Only the physical state of the salt changes, as it goes from being a solid to being dispersed and mixed with water molecules. The process of dissolving is a physical change because it does not involve any chemical reactions or the formation of new substances.

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27.

Which of the following is NOT a property of acids?
- Sour taste
- Turns blue litmus paper red
- Reacts with metals to produce hydrogen gas
- Feels slippery
Correct Answer

A. Feels slippery

Explanation

Acids are known for their sour taste, their ability to turn blue litmus paper red, and their reactivity with metals to produce hydrogen gas. Bases, on the other hand, feel slippery to the touch.

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0
28.

Rusting is classified as:
- Physical change
- Chemical change
Correct Answer

A. Chemical change

Explanation

Rusting is classified as a chemical change because it involves a chemical reaction between iron and oxygen in the presence of moisture. This reaction leads to the formation of iron oxide, which is a different substance with different properties than the original iron. The change is not reversible and involves the breaking and forming of chemical bonds. Therefore, rusting is considered a chemical change rather than a physical change.

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29.

Molecules in a solid are arranged as follows:
- Spaced out and free to slide over each other
- Very spaced out and free to move from one ion to another
- Packed together and can only vibrate
- None of the above
Correct Answer

A. Packed together and can only vibrate

Explanation

The correct answer is "packed together and can only vibrate." In a solid, the molecules are closely packed together and are held in a fixed position. They are not free to slide over each other like in a liquid, nor can they move from one ion to another like in an ionic compound. Instead, the molecules in a solid can only vibrate in their fixed positions. This arrangement gives solids their characteristic rigidity and shape.

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30.

Water is an example of:
- Compound
- Element
- Atom
- Mixture
Correct Answer

A. Compound

Explanation

Water is an example of a compound because it is made up of two different elements, hydrogen and oxygen, chemically bonded together. In a compound, the elements are combined in a fixed ratio and cannot be separated by physical means. Water molecules consist of two hydrogen atoms bonded to one oxygen atom, forming the chemical formula H2O. Therefore, water fits the definition of a compound.

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2
31.

In the periodic a group of family is described as:
- Horizontal rows
- Diagonal rows
- Vertical columns
- None of the above
Correct Answer

A. Vertical columns

Explanation

The correct answer is "vertical columns" because in the periodic table, elements are arranged in columns called groups or families. These groups have similar properties and characteristics, as they have the same number of valence electrons. The vertical arrangement allows for easy comparison and identification of elements with similar chemical behavior. Therefore, the description of a group or family in the periodic table is vertical columns.

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0
32.

Period go from:
- Top to bottom
- Left to right
Correct Answer

A. Left to right

Explanation

The period goes from left to right. This means that when arranging elements in a periodic table, they are placed in order of increasing atomic number from left to right across each row.

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0
33.

The symbol of magnesium is:
- Mn
- M
- Mo
- Mg
Correct Answer

A. Mg

Explanation

The correct answer is Mg. Magnesium is a chemical element with the symbol Mg. It is a shiny gray solid and is commonly found in minerals such as magnesite and dolomite. Magnesium is known for its lightness and is used in various industries, including aerospace and automotive.

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1
34.

The symbol of copper is:
- Co
- Cu
- C
- Cp
Correct Answer

A. Cu

Explanation

The correct answer is Cu because Cu is the chemical symbol for copper. Chemical symbols are used to represent elements in the periodic table, and Cu specifically represents copper.

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35.

What is the name of the element with symbol Sr:
- Sodium
- Silicon
- Scandium
- Strontium
Correct Answer

A. Strontium

Explanation

The correct answer is strontium. Strontium is an element with the symbol Sr on the periodic table. It is a silvery-white alkaline earth metal that is highly reactive and is commonly used in fireworks and flares. It is also found in some minerals and is used in the production of glass and ceramics.

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2
36.

In what period does iodine belong to:
- 5
- 4
- 3
- 2
- 1
Correct Answer

A. 5

Explanation

Iodine belongs to period 5 on the periodic table because the period number corresponds to the number of energy levels or electron shells in an atom. Iodine has 5 energy levels, so it is located in period 5.

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1
37.

An example of a transition element is:
- Sodium
- Scandium
- Aluminum
- Argon
Correct Answer

A. Scandium

Explanation

Scandium is an example of a transition element because it meets the criteria for being classified as one. Transition elements are located in the d-block of the periodic table, and they have partially filled d orbitals. Scandium fits these criteria as it is located in the d-block and has a partially filled 3d orbital. Additionally, transition elements often exhibit multiple oxidation states and form colorful compounds, which scandium also demonstrates. Therefore, scandium is a suitable example of a transition element.

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1
38.

An example of alkali metal is:
- K
- Ca
- P
- Cl
- Au
Correct Answer

A. K

Explanation

K is an example of an alkali metal. Alkali metals are the elements found in Group 1 of the periodic table. They are highly reactive and have only one valence electron, which they readily donate to form positive ions. K represents potassium, which is a soft, silvery-white metal. It is highly reactive and reacts vigorously with water, producing hydrogen gas. Potassium compounds are widely used in fertilizers, medicines, and industrial applications.

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1
39.

An example of a noble gas is:
- N
- Na
- Ne
- No
Correct Answer

A. Ne

Explanation

Neon (Ne) is an example of a noble gas. Noble gases are a group of elements in the periodic table that have full valence electron shells, making them stable and unreactive. Ne is in the group 18 (VIII A) of the periodic table and has a full valence electron shell with 8 electrons, making it unreactive and inert. It is colorless, odorless, and commonly used in neon signs due to its ability to emit a bright orange-red light when an electric current is passed through it.

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40.

An example of a hallogen is:
- Ca
- Co
- Br
- S
Correct Answer

A. Br

Explanation

Bromine (Br) is an example of a halogen. Halogens are a group of highly reactive elements that belong to Group 17 of the periodic table. They include fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At). These elements have seven valence electrons and tend to gain one electron to achieve a stable electron configuration. Bromine is a reddish-brown liquid at room temperature and is commonly used in flame retardants, disinfectants, and pharmaceuticals. It is highly reactive and can form compounds with a wide range of other elements.

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1
41.

The electron configuration of phosphorus is:
- 2,8,1
- 2,8,4
- 2,8,7
- 2,8,5
Correct Answer

A. 2,8,5

Explanation

The electron configuration of an atom represents the arrangement of electrons in its energy levels. Phosphorus has 15 electrons, and the electron configuration is determined by filling up the energy levels in order of increasing energy. The first energy level can hold a maximum of 2 electrons, the second energy level can hold a maximum of 8 electrons, and the third energy level can hold a maximum of 8 electrons as well. Therefore, the electron configuration of phosphorus is 2,8,5, as it has 2 electrons in the first energy level, 8 electrons in the second energy level, and 5 electrons in the third energy level.

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1
42.

Electron in the outer shell is called:
- Bonding electron
- Transferred electron
- Valence electron
- All of the above
Correct Answer

A. Valence electron

Explanation

The electron in the outer shell of an atom is called a valence electron. Valence electrons are involved in the formation of chemical bonds and determine the reactivity and chemical properties of an atom. They can be shared, transferred, or involved in bonding with other atoms. Therefore, the correct answer is "valence electron".

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1
43.

How many valence electrons are present in an oxygen atom:
- 4
- 5
- 6
- 7
- 8
Correct Answer

A. 6

Explanation

An oxygen atom has 6 valence electrons. Valence electrons are the electrons in the outermost energy level of an atom, and they are responsible for the atom's chemical properties and its ability to form bonds with other atoms. Oxygen has 6 electrons in its outermost energy level, which is the 2p orbital.

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44.

Which of the following pair belong in the same group:
- Na and Ca
- Si and Al
- C, Ge
- S, Cl
Correct Answer

A. C, Ge

Explanation

C and Ge belong in the same group because they both belong to Group 14 on the periodic table, also known as the carbon group. This group consists of elements that have similar chemical properties and share certain characteristics. Both C (carbon) and Ge (germanium) are nonmetals and have similar valence electron configurations, making them part of the same group.

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45.

Where are the most active metals located?
- Upper right hand side
- Bottom left hand side
- Upper lefthand side
- Bottom right hand side
Correct Answer

A. Bottom left hand side

Explanation

The most active metals are located in the bottom left hand side of the periodic table. This is because as you move from left to right across a period, the metals become less reactive. On the other hand, as you move down a group, the metals become more reactive. Therefore, the bottom left hand side of the periodic table is where you will find the most active metals.

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0
46.

As you go from left to right across a period, the atomic size:
- Increases
- Decreases
- Stay thesame
Correct Answer

A. Decreases

Explanation

Increase in nuclear charge shrinks the atoms as we move from left to right.

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0
47.

50. As you travel down a group, the atomic size:
- Increases
- Decreases
- Stay the same
Correct Answer

A. Increases

Explanation

Because of the increase in nuclear charge.

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1
48.

Elements within a group have a similar number of:
- Shells
- Electrons
- Valence electrons
- Atomic mass
Correct Answer

A. Valence electrons

Explanation

Elements within a group have a similar number of valence electrons. Valence electrons are the electrons in the outermost energy level of an atom and are responsible for the chemical behavior of the element. Elements within the same group have the same number of valence electrons because they are in the same column of the periodic table. This similarity in valence electrons allows elements within a group to exhibit similar chemical properties and react in similar ways.

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49.

Elements across a period have the same number of:
- Shells
- Valence electrons
- Atomic mass
- Protons
Correct Answer

A. Shells

Explanation

Elements across a period have the same number of shells. This is because elements in the same period have the same number of energy levels or electron shells. As you move across a period from left to right, the number of protons and valence electrons increases, but the number of shells remains the same. Therefore, the correct answer is shells.

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The Ultimate Chemistry Exams Prep Test

Convert 20g to kg.

Quiz Preview

Convert 23ml to liters.

Convert 18km to mm.

Convert 88kg to mg.

Convert 23.6cm to mm.

Define matter:

Name the three states of matter:

What instruments do we use to measure volume?

What instruments do we use to measure the mass:

What instruments do we use to measure density?

What SI unit is used to measure volume

Properties that cannot be observed with the five senses are called:

A substance consisting of two elements chemically combined is known as:

A mixture that separate into two visible phases is known as:

A positive charge particle found in the nucleus is called:

A change from liquid to solid is called:

A change from liquid to gas is known as:

A change from gas to liquid is called:

A mixture of sand and iron particles can be separated by:

A mixture of salt and water can be separated by:

A mixture of sand and water can be separated by:

A mixture of peroxide and water can be separated by:

Burning wood is an example of:

Baking cake is classified as:

Melting candle wax is classified as:

Dissolving salt in water is classified as:

Which of the following is NOT a property of acids?

Rusting is classified as:

Molecules in a solid are arranged as follows:

Water is an example of:

In the periodic a group of family is described as:

Period go from:

The symbol of magnesium is:

The symbol of copper is:

What is the name of the element with symbol Sr:

In what period does iodine belong to:

An example of a transition element is:

An example of alkali metal is:

An example of a noble gas is:

An example of a hallogen is:

The electron configuration of phosphorus is:

Electron in the outer shell is called:

How many valence electrons are present in an oxygen atom:

Which of the following pair belong in the same group:

Where are the most active metals located?

As you go from left to right across a period, the atomic size:

50. As you travel down a group, the atomic size:

Elements within a group have a similar number of:

Elements across a period have the same number of: