Kobe is testing whether 100 g of substance a, 100 g of substance b, or 100 g of substance c produces more oxygen in a chemical reaction at 25â°c. what is the independent variable? a) the nature of the substances. b) the masses of the substances. c) the amount of oxygen produced. d) the temperature of the substance.

Option (a) is the correct answer.

Explanation:

An independent variable is defined as a variable whose value or which is controlled in a scientific experiment. Basically, an independent variable is able to change the value of dependent variable.

The value of an independent variable can be changed by the experimenter.

For example, nature of substances in a chemical reaction will act as an independent variable.

This is because if a substance is reactive in nature then in the presence of another substance cannot become unreactive. Hence, nature of a substance is an independent variable.

Thus, we can conclude that out of the given options the nature of the substances is the independent variable.

wher is the rest of the question

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.