Calcium carbonate breaks down on heating to produce calcium oxide and carbon dioxide gas. CaCO3 ® CaO + CO2

A student heats 15 g of calcium carbonate strongly in a crucible.

Relative atomic masses (Ar): Ca = 40, C = 12, O = 16.

4 / 4

a Calculate the number of moles in 15 g of calcium carbonate. (2 marks)

b Use your answer to part a to determine the number of moles of calcium oxide that will be produced. (1 mark)

c Calculate the mass of calcium oxide produced by this reaction. (2 marks)

4 A student is preparing a sample of sodium nitrate, NaNO3.

She mixes 17 g of sodium oxide with an excess of nitric acid. The equation for the reaction is:

Na2O + 2HNO3 ® 2NaNO3 + H2O

Relative atomic masses (Ar): Na = 23, O = 16, N = 14, H = 1.

a Calculate the number of moles in 17 g of sodium oxide. (2 marks)

b Calculate the maximum mass of sodium nitrate that can be produced in this reaction. (3 marks)

5 Aluminium and iron oxide (Fe2O3) react together to produce aluminium oxide (Al2O3). The equation for the reaction is:

2Al + Fe2O3 ® Al2O3 + 2Fe

Calculate the mass of iron that is produced by reacting 20 g of iron oxide with an excess of aluminium.

Relative atomic masses (Ar): Al = 27, O = 16, Fe = 56. (4 marks)

solute : a solute is a substance that is dissolved in another substance is known as a solvent. it is mixed with a special mixture know as homogeneous mixture.

solvent: a solvent is a substance that dissolved a solute, which results in a solution is known as solvent.

it forms an anion that has a larger radius. anions have a negative charge and are larger than the original atom.

i think its 100.

hope this !

explanation:

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.

two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.