Question

question 8
1 pts
when the reaction shown is correctly balanced, the coefficients are:
$(nh_{4})_{2}so_{4}(aq)+ba(c_{2}h_{3}o_{2})_{2}(aq)\to baso_{4}(s)+nh_{4}c_{2}h_{3}o_{2}(aq)$
$2,1,2,1$
$1,2,1,1$
$1,2,2,1$
$1,1,1,2$
$1,1,1,1$

question 9
1 pts
the balanced equation for the reaction occurring when calcium nitrate solution
is mixed with sodium phosphate solution is:
$3ca(no_{3})_{2}(aq)+2na_{3}po_{4}(aq)\to ca_{2}(po_{4})_{3}(s)+6nano_{3}(aq)$
$3ca(no_{3})_{2}(aq)+2na_{3}po_{4}(aq)\to ca_{3}(po_{4})_{2}(s)+6nano_{3}(aq)$
$2cano_{3}(aq)+3na_{3}po_{4}(aq)\to ca_{2}(po_{4})_{3}(s)+2nano_{3}(aq)$
$2ca(no_{3})_{2}(aq)+3na_{3}po_{4}(aq)\to 2ca_{3}(po_{4})_{2}(s)+6nano_{3}(aq)$

Explanation:

Question 8

Step1: Balance the reaction

The given reaction is \((NH_4)_2SO_4(aq)+Ba(C_2H_3O_2)_2(aq)\to BaSO_4(s)+NH_4C_2H_3O_2(aq)\)

For \(NH_4\) group: On the left - hand side, there are \(2\) \(NH_4\) groups in \((NH_4)_2SO_4\). On the right - hand side, there is \(1\) \(NH_4\) group in \(NH_4C_2H_3O_2\). So, we put a coefficient of \(2\) in front of \(NH_4C_2H_3O_2\)

The balanced equation is \((NH_4)_2SO_4(aq)+Ba(C_2H_3O_2)_2(aq)\to BaSO_4(s)+2NH_4C_2H_3O_2(aq)\)

The coefficients are \(1,1,1,2\)

Question 9

Step1: Write the un - balanced equation

Calcium nitrate is \(Ca(NO_3)_2\), sodium phosphate is \(Na_3PO_4\). The reaction between them is a double - displacement reaction. The un - balanced equation is \(Ca(NO_3)_2(aq)+Na_3PO_4(aq)\to Ca_3(PO_4)_2(s)+NaNO_3(aq)\)

Step2: Balance \(Ca\) atoms

On the left - hand side, there is \(1\) \(Ca\) atom in \(Ca(NO_3)_2\), and on the right - hand side, there are \(3\) \(Ca\) atoms in \(Ca_3(PO_4)_2\). So, we put a coefficient of \(3\) in front of \(Ca(NO_3)_2\)

The equation becomes \(3Ca(NO_3)_2(aq)+Na_3PO_4(aq)\to Ca_3(PO_4)_2(s)+NaNO_3(aq)\)

Step3: Balance \(PO_4\) groups

On the left - hand side, there is \(1\) \(PO_4\) group in \(Na_3PO_4\), and on the right - hand side, there are \(2\) \(PO_4\) groups in \(Ca_3(PO_4)_2\). So, we put a coefficient of \(2\) in front of \(Na_3PO_4\)

The equation is \(3Ca(NO_3)_2(aq)+2Na_3PO_4(aq)\to Ca_3(PO_4)_2(s)+NaNO_3(aq)\)

Step4: Balance \(Na\) and \(NO_3\) groups

On the left - hand side, there are \(6\) \(Na\) atoms (from \(2Na_3PO_4\)) and \(6\) \(NO_3\) groups (from \(3Ca(NO_3)_2\)). On the right - hand side, we put a coefficient of \(6\) in front of \(NaNO_3\)

The balanced equation is \(3Ca(NO_3)_2(aq)+2Na_3PO_4(aq)\to Ca_3(PO_4)_2(s)+6NaNO_3(aq)\)

Answer:

Question 8: \(1,1,1,2\) (the fourth option)
Question 9: \(3Ca(NO_3)_2(aq)+2Na_3PO_4(aq)\to Ca_3(PO_4)_2(s)+6NaNO_3(aq)\) (the second option)