A sample of gallium bromide, GaBr3, weighing 0.165 g was dissolved in water and treated with silver nitrate, AgNO3, resulting in the precipitation of 0.299 g AgBr. Use these data to compute the %Ga (by mass) GaBr3.

%Ga by mass in sample of is 23.0%

Explanation:

Molar mass of AgBr = 187.77 g/mol

So, 0.299 g of AgBr = moles of AgBr = moles of Br = 0.00159 moles of Br

Br in AgBr comes from

So, there are 0.00159 moles of Br in 0.165 g of

Molar mass of Br = 79.904 g/mol

So, mass of Br in 0.165 g of = = 0.127 g

So, mass of Ga in sample of = (0.165-0.127) g = 0.038 g

So, %Ga by mass in sample of = [(mass of Ga)/(mass of )]%

                                                              = %

                                                              = 23.0%

acid rain does not usually kill trees directly. instead, it is more likely to weaken the trees by damaging their leaves, limiting the nutrients available to them, or poisoning them with toxic substances slowly released from the soil. the main atmospheric pollutants that affect trees are nitrates and sulphates.