Conservation of Mass

Q.

Mass of reactants is equal to mass of products if the reaction has same number of atoms of different elements on either side of the chemical equation respectively.

1. True

2. False

Q.

Gram molecular weight of $N{H}_3$ is:

1. 16

2. 17

3. 9

4. 18

Q. Why is it necessary to balance the number of atoms on the two sides of a skeletal chemical equation?

1. Law of conservation of mass
2. The number of atoms are representative of the mass of each element on each side of a chemical reaction
3. The skeletal equation does not show all the elements
4. There has to be a difference between skeletal and balanced equation.

Q. Which of the following law is obeyed during the balancing of a chemical equation?

1. Conservation of energy
2. Conservation of inertia
3. Periodic Law
4. Conservation of mass

Q.

Consider the following reaction.

$Cu(N{O}_3{)}_2\to CuO+N{O}_2+O_2$ Which of the following are correct?

1. Mass of products = mass of reactants

2. Number of atoms on either side of the reaction are equal

3. Mass of reactants is not equal to mass of products

4. Number of atoms on product side is more than the reactant side.

Q.

Mass is not conserved in a chemical reaction.

1. True

2. False

Q.

In an experiment, 15 gm of a compound X is heated in a closed glass container to give compounds Y and Z. The total mass of the compounds Y and Z is ______.

1. 15

2. 20

3. 10

4. 30

Q. Which of the following law is obeyed during the balancing of a chemical equation?

1. Conservation of energy
2. Conservation of inertia
3. Periodic Law
4. Conservation of mass

Q. Total mass of ___ = Total mass of products

Q. What indicates that a chemical reaction has occurred? [3 Mark]