Sulfuric acid (H2SO4) has a molar mass of 98.1 g/mol. How many oxygen atoms are found in 75.0 g of H2SO4?

18.33 ×10²³ atoms

Explanation:

Given data:

Molar mass of sulfuric acid = 98.1 g/mol

Mass of sulfuric acid = 75.0 g

Number of of oxygen atom present = ?

Solution:

Number of moles of sulfuric acid:

Number of moles = mass/molar mass

Number of moles = 75.0 g/ 98.1 g/mol

Number of moles =0.761 mol

one mole of  sulfuric acid  contain four mole of oxygen atom.

0.761 mol × 4 = 3.044 mol

1 mole = 6.022×10²³ atoms of oxygen

3.044 mol ×  6.022×10²³ atoms of oxygen / 1mol

18.33 ×10²³ atoms

answer: c. the experiment shows that the red substance experienced a chemical change.

explanation: chemical change is the change in which chemical composition of the substance changes. physical change is the change in which there is no change in chemical composition.

chemical changes are accompanied by following changes:

a) precipitate formation

b) energy is released or absorbed

c) formation of bubbles

d) change in color

as it is given that the red color has disappeared and there is production of gas, it means the red substance has undergone a chemical change.

e

a) the particles of the chair are strongly held together.