Tin (sn) exists in earth's crust as sno2. calculate the percent composition by mass of sn and o in sno2.

Sn = 78.77%

O = 21.23%

Explanation:

The atomic mass of Sn = 118.71 g/mol

The atomic mass of O = 16 g/mol

The molar mass of SnO₂ = atomic mass of Sn + 2 X atomic mass of O

The molar mass of SnO₂= 150.71

Now, in each mole of SnO₂ there is one mole of Sn and two moles of O

The mass of Sn in 150.71 g of SnO₂ = 118.71

Percentage of Sn in 150.71 g of SnO₂ =

% of Sn = %.

Rest will be O = 100-78.77 = 21.23%

in 1783 cavendish was working with his hydrogen gas and found that when he burned it and condensed the vapor it was water. this was very significant since it disproved the greek theory of elements completely since water was not a simple substance but the product of two gases. it was lavoisier who hearing of the experiment gave cavendish's gas the name hydrogen ("water-producer") and added that hydrogen burned by combining with oxygen and that water was a hydrogen-oxygen combination.

explanation: