Senior One Task No5

Approved & Edited by ProProfs Editorial Team
The editorial team at ProProfs Quizzes consists of a select group of subject experts, trivia writers, and quiz masters who have authored over 10,000 quizzes taken by more than 100 million users. This team includes our in-house seasoned quiz moderators and subject matter experts. Our editorial experts, spread across the world, are rigorously trained using our comprehensive guidelines to ensure that you receive the highest quality quizzes.
Learn about Our Editorial Process
| By Nema
N
Nema
Community Contributor
Quizzes Created: 2 | Total Attempts: 187
Questions: 15 | Attempts: 94

SettingsSettingsSettings
Chemistry Quizzes & Trivia

.


Questions and Answers
  • 1. 

    1. in the following reaction: 8Zn + S8 ------------ 8ZnS calculate: the mass of zinc sulphide which is resulted with an excess amount of zinc. (zn=65 , s=32 )

  • 2. 

    -calculate the volume of oxygen needed to produce 90 g of water by reacting with an excess amount of hydrogen at STP. (o=16 , H=1) 2H2 + O2 -------------------2H2O

  • 3. 

    1-all the neutralization reaction are considered as a combination between…………. To form H2O

    • A.

      H+ and OH

    • B.

      OH- and OH-

    Correct Answer
    A. H+ and OH
    Explanation
    Neutralization reactions occur when an acid reacts with a base to form water and a salt. In this case, the correct answer is "H+ and OH". This is because in a neutralization reaction, the H+ ions from the acid combine with the OH- ions from the base to form water (H2O). The other options, "OH- and OH-" and "OH- and OH-", do not involve the H+ ions necessary for the formation of water in a neutralization reaction.

    Rate this question:

  • 4. 

    2- one mole of any substance contains …………molecules.

    • A.

      6.02 x 1023

    • B.

      6.02 x 10-23

    Correct Answer
    A. 6.02 x 1023
    Explanation
    One mole of any substance contains 6.02 x 10^23 molecules. This is known as Avogadro's number and represents the number of particles (atoms, molecules, ions, etc.) in one mole of a substance. It is a fundamental constant in chemistry and is used to convert between the mass of a substance and the number of particles it contains.

    Rate this question:

  • 5. 

    3-the no. of atoms of 0.5 moles of sodium is ………………… atoms

    • A.

      3.01 x 10power 23 ,

    • B.

      6.02 x10power 23

    Correct Answer
    A. 3.01 x 10power 23 ,
    Explanation
    The answer is 3.01 x 10^23 atoms. This is because 1 mole of any substance contains 6.02 x 10^23 particles (Avogadro's number). Therefore, 0.5 moles of sodium would contain half of that amount, which is 3.01 x 10^23 atoms.

    Rate this question:

  • 6. 

    1. which of the following, heat energy will be evolved?

    • A.

      Dissolution of NH4Cl in water

    • B.

      Burning of L.P.G.

    Correct Answer
    B. Burning of L.P.G.
    Explanation
    Burning of L.P.G. involves a chemical reaction called combustion, which releases heat energy as a byproduct. This process is exothermic, meaning it releases energy in the form of heat. On the other hand, dissolution of NH4Cl in water is an endothermic process, which means it absorbs heat energy from the surroundings instead of releasing it. Therefore, the correct answer is burning of L.P.G.

    Rate this question:

  • 7. 

    Conservation of mass is obtained when total mass of reactants is equal to total mass of

    • A.

      Molecules

    • B.

      Products

    Correct Answer
    B. Products
    Explanation
    Conservation of mass is a fundamental principle in chemistry that states that the total mass of the reactants in a chemical reaction is equal to the total mass of the products. This means that no mass is created or destroyed during a chemical reaction, but rather it is rearranged to form new substances. Therefore, the correct answer is "products" because the total mass of the products should be equal to the total mass of the reactants for conservation of mass to hold true.

    Rate this question:

  • 8. 

    the Molar volume At Stp is ………………approxemtailly

    • A.

      22

    • B.

      24

    Correct Answer
    A. 22
    Explanation
    The molar volume at STP is approximately 22. This is because at standard temperature and pressure (STP), one mole of any ideal gas occupies a volume of approximately 22.4 liters. Since the question asks for an approximate value, 22 is the closest option to the actual value of 22.4.

    Rate this question:

  • 9. 

    choose the suitable balance for the following Equation FeBr3 + H2SO4 ------- Fe2(SO4)3 + HBr

    • A.

      2-3-1-6

    • B.

      2-4-1-5

    Correct Answer
    A. 2-3-1-6
    Explanation
    The suitable balance for the given equation is 2-3-1-6. This means that there are 2 FeBr3 molecules reacting with 3 H2SO4 molecules to produce 1 Fe2(SO4)3 molecule and 6 HBr molecules. This balance ensures that the number of atoms of each element is equal on both sides of the equation, satisfying the law of conservation of mass.

    Rate this question:

  • 10. 

    Calculate the molar mass of anhydrous copper sulphate CUSO4 . 5H2O is ................. nearstly  

    • A.

      250

    • B.

      200

    Correct Answer
    A. 250
    Explanation
    The molar mass of anhydrous copper sulphate (CUSO4) can be calculated by adding up the atomic masses of each element in the compound. Copper (Cu) has an atomic mass of 63.55 g/mol, sulfur (S) has an atomic mass of 32.07 g/mol, and oxygen (O) has an atomic mass of 16.00 g/mol. Therefore, the molar mass of CUSO4 is 63.55 + 32.07 + (16.00 * 4) = 159.62 g/mol. Since the compound also contains 5 water molecules (H2O), each with a molar mass of 18.02 g/mol, we need to add that to the molar mass. 159.62 + (18.02 * 5) = 250.12 g/mol. Therefore, the molar mass of anhydrous copper sulphate is approximately 250 g/mol.

    Rate this question:

  • 11. 

    the element which written in the reaction are written in form of …

    • A.

      Symbol

    • B.

      Compound

    Correct Answer
    A. Symbol
    Explanation
    In chemical reactions, the elements involved are typically written in the form of symbols. This is because symbols represent the individual elements and make it easier to identify and understand the reaction. Writing the elements in the form of compounds would involve combining multiple elements together, which may not accurately represent the reaction. Therefore, using symbols is the correct way to write the elements in a reaction.

    Rate this question:

  • 12. 

    Calculate the number of molecules that are found in a sample of sulphur dioxide of mass 32 g [S=32 . O = 16]

    • A.

      2NA

    • B.

      HALF NA

    Correct Answer
    B. HALF NA
    Explanation
    The given answer "HALF NA" suggests that the number of molecules found in the sample of sulphur dioxide is half of Avogadro's number (NA). Avogadro's number represents the number of particles (atoms, molecules, ions, etc.) in one mole of a substance. Since the molar mass of sulphur dioxide (SO2) is 64 g/mol (32 g for sulphur + 32 g for oxygen), and the given mass is 32 g, it means we have 0.5 moles of SO2. Therefore, the number of molecules can be calculated by multiplying the moles by Avogadro's number and then dividing by 2, giving us half of NA.

    Rate this question:

  • 13. 

    molar mass of hydrogen gas is ……………………

    • A.

      Mass of 6.02x1023molc

    • B.

      Mass of 12.04x1023 atoms

    • C.

      All

    Correct Answer
    C. All
    Explanation
    The molar mass of hydrogen gas can be calculated by considering the mass of 6.02x10^23 molecules or the mass of 12.04x10^23 atoms. Both methods will give the same result, so the correct answer is "all".

    Rate this question:

  • 14. 

    9-………law is states that : at constant temperature volume of gas is directly prop. With no. of moles.

    • A.

      Avogadro's law

    • B.

      Gases law

    • C.

      Temperature law

    Correct Answer
    A. Avogadro's law
    Explanation
    Avogadro's law states that at a constant temperature and pressure, the volume of a gas is directly proportional to the number of moles of gas present. This means that as the number of moles of gas increases, the volume of the gas also increases proportionally. Therefore, Avogadro's law is the correct answer to the question.

    Rate this question:

  • 15. 

    Chemical change involves formation of

    • A.

      New substances

    • B.

      Salt

    • C.

      Water

    Correct Answer
    A. New substances
    Explanation
    Chemical change refers to a process where one or more substances are transformed into different substances with new properties. In this case, the formation of new substances is the correct answer because it accurately describes the fundamental characteristic of a chemical change. The formation of salt and water mentioned in the question is an example of a chemical change, as it involves the combination of different elements (such as sodium and chlorine) to form a new compound (salt) and the reaction between hydrogen and oxygen to produce water.

    Rate this question:

Back to Top Back to top
Advertisement
×

Wait!
Here's an interesting quiz for you.

We have other quizzes matching your interest.