1.
Which describes a compound?
Correct Answer
C. 2 different atoms chemically connected together
Explanation
A compound is a substance that is made up of two or more different atoms chemically bonded together. This means that the atoms are connected through chemical bonds, such as covalent or ionic bonds, to form a new substance with unique properties. This is different from a pure collection of one type of atom, which would be an element, and from two items physically mixed together, which would be a mixture.
2.
Which property describes an acid?
Correct Answer
D. Litmus Red
Explanation
Litmus Red is the correct answer because it is a property that specifically describes an acid. Litmus paper is commonly used to test the acidity or alkalinity of a substance. When an acid is present, the litmus paper turns red, indicating its acidic nature. Therefore, Litmus Red is the property that describes an acid.
3.
The material has no definite shape but a definite volume. What state of matter is it?
Correct Answer
B. Liquid
Explanation
A substance that has no definite shape but a definite volume is a liquid. Unlike solids, liquids are not rigid and can flow and take the shape of their container. However, they still have a fixed volume, meaning they cannot be compressed like gases. Plasma, on the other hand, is an ionized gas and does not have a definite volume. Therefore, the correct answer is liquid.
4.
Which property is NOT a physical change?
Correct Answer
A. Corroding
Explanation
Corroding is a chemical change, not a physical change. Physical changes involve a change in the state or form of matter without altering its chemical composition. Corroding, on the other hand, is a chemical process that occurs when a substance reacts with its environment, leading to the breakdown of the material. This chemical reaction results in the formation of new substances with different chemical properties. Therefore, corroding is not considered a physical change.
5.
Which is a compound?
Correct Answer
C. Water
Explanation
Water is a compound because it is composed of two different elements, hydrogen and oxygen, chemically bonded together. This is evident in its chemical formula, H2O, which represents the ratio of two hydrogen atoms to one oxygen atom in a water molecule. In contrast, oxygen and carbon are both elements, and soup is a mixture of various ingredients rather than a pure substance.
6.
Which chemical is organic?
Correct Answer
A. C6H12O6
Explanation
It contains carbon - but also hydrogen and oxygen.
7.
Which material is considered pure matter?
Correct Answer(s)
A. Element
C. Compound
Explanation
An element is considered pure matter because it consists of only one type of atom. It cannot be broken down into simpler substances by chemical means. Compounds, on the other hand, are made up of two or more different elements chemically combined. Mixtures are a combination of two or more substances that are physically mixed together but not chemically bonded. Therefore, elements are the purest form of matter as they are composed of identical atoms. Compounds and mixtures, on the other hand, contain different types of atoms or substances.
8.
What is the freezing point of this material?
Correct Answer
B. 5
Explanation
The freezing point of a material refers to the temperature at which it changes from a liquid state to a solid state. In this case, the freezing point of the material is given as 5. This means that the material will freeze and solidify at a temperature of 5 degrees.