Question

A. Choose the correct option.
1. The substances initially involved in a chemical reaction are
c. reactants.
b. reactors.
a. products.
d . catalysts
2. In an exothermic reaction, the temperature
a. remains the same. b. rises. c. falls . d. may rise or fall
3. During a chemical reaction, the arrow pointing upwards shows the
a. formation of products.
b. precipitation of a substance.
c. rise in temperature.
d. evolution of gas.
4. Which of the following is not a characteristic of a chemical reaction?
a. Change of size
b. Change of state
c. Heat absorbed
d. Formation of precipitate
5. The formation of gas bubbles with a sound in a solution is called
a. physical change.
b. effervescence.
c. precipitation
d. chemical reaction.
​

Answer 1

Answer:

1. The substances initially involved in a chemical reaction are:

Ans: Reactants.

2. In an exothermic reaction, the temperature:

Ans: Rises.

3. During a chemical reaction, the arrow pointing upwards shows the:

Ans: Evolution of gas.

4. Which of the following is not a characteristic of a chemical reaction?

Ans: Formation of precipitation.

5.The formation of gas bubbles with a sound in a solution is called:

Ans: Precipitation.