Q. 7.26 - An Introduction to General, Organic, and Biological Chemistry

Question

Calculate the number of moles in each of the following: 

a. $85.2$ g of $Ni$ 

b. $144$g of $K$

 c. $6.4$g of $H_{2}O$

d. $308$g of$BaS{O}_4$

e. $252.8$g of fructose, $C_6{H}_{12}{O}_6$

Step-by-Step Solution

Answer

The number of moles in each of the following:  

 a.   $1.45$ moles

b .$3.68$ moles

c.  $0.35$ moles

d.$1.32$ moles

e.$1.40$ moles

Part (a) Step 1: Given information

We need to find number of moles in $85.2$ g of $Ni$ .

Part (a) Step 2: Explanation

Here, we need to calculate number of moles , we will use the formula for number of moles

We are given with the gram molecular weight , and we know the molar mass for this element , so we get ;

Number of moles=gram molecular weight/molar mass 

Therefore, $\frac{85.2 \cancel{g} }{58.69\cancel{ g}/moles} =1.45$ moles

Part (b) Step 1: Given information

We need to find number of moles of $144$ g of$K$ .

Part (b) Step 2: Explanation

Here, we need to calculate number of moles , we will use the formula for number of moles

We are given with the gram molecular weight , and we know the molar mass for this element , so we get ;

Number of moles=gram molecular weight/molar mass 

Therefore, $\frac{144\cancel{ g}}{39.09\cancel{ g}/moles}=3.68$ moles

Part (c) Step 1: Given information

We need to find number of moles of $6.4$g of $H_{2}O$.

Part (c) Step 2: Explanation

Here, we need to calculate number of moles , we will use the formula for number of moles

We are given with the gram molecular weight , and we know the molar mass for this element , so we get ;

Number of moles=gram molecular weight/molar mass 

Therefore,$\frac{6.4\cancel{ g}}{18\cancel{ g}/moles}=0.35$ moles

Part (d) Step 1: Given information

We need to find number of moles of $308$g of $BaS{O}_4$ .

Part (d) Step 2: Explanation

Here, we need to calculate number of moles , we will use the formula for number of moles

We are given with the gram molecular weight , and we know the molar mass for this element , so we get ;

Number of moles=gram molecular weight/molar mass 

Therefore,$\frac{308 \cancel{g}}{233\cancel{ g}/moles}=1.32$ moles

Part (e) Step 1: Given information

We need to find number of moles of $252.8$gof fructose .

Part (e) Step 2: Explanation

Here, we need to calculate number of moles , we will use the formula for number of moles

We are given with the gram molecular weight , and we know the molar mass for this element , so we get ;

Number of moles=gram molecular weight/molar mass 

Therefore,$\frac{252.8\cancel{ g}}{180.1\cancel{ g}/moles}=1.40$ moles