How many grams of Br are in 105 g CaBrz?

I hope this helps 0w0

Explanation:

Explanation:

In order to figure out how many grams of bromine you get in that many grams of calcium bromide,  

CaBr

2

, you must find the compound's percent composition.  

To do that, use the fact that one mole of calcium bromide contains

one mole of calcium cations,  

Ca

2

+

two moles of bromide anions,  

2

×

Br

−

You can thus us the molar mass of calcium bromide and the molar mass of bromine to determine how many grams of bromine you get per  

100 g

of calcium bromide.  

The two molar mass are

For CaBr

2

:

M

M

=

199.89 g mol

−

1

For Br:

M

M

=

79.904 g mol

−

1

So, two moles of bromide anions for every one mole of calcium bromide will give you a percent composition of  

2

×

79.904

g mol

−

1

199.89

g mol

−

1

×

100

=

79.95% Br

This means that every  

100 g

of calcium bromide will contain  

79.95 g

of elemental bromine in the form of bromide cations.  

All you have to do now is use this percent composition as a conversion factor to determine how many grams of bromine you get in that  

195-g

sample of calcium bromide

195

g CaBr

2

⋅

79.95% Br



79.95 g Br

100

g CaBr

2

=

∣

∣

∣

∣

¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

a

a

156 g Br

a

a

∣

∣

−−−−−−−−−−−−