Question

When $MgC{l}_2\cdot 6H_{2}O$ is strongly heated, then it forms:

• A. $MgO$
• B. $Mg(OH{)}_2$
• C. $Mg\left(OH\right)Cl$
• D. $MgC{l}_2$

Answer 1

The correct option is A $MgO$

When $MgC{l}_2\cdot 6H_{2}O$ is strongly heated, then it forms $MgO$.
On heating, $MgC{l}_2\cdot 6H_{2}O$ readily loses 4 molecules of water of crystallization to form $MgC{l}_2\cdot 2H_{2}O$.
$MgC{l}_2\cdot 6H_{2}O\stackrel{\Delta }{\to }MgC{l}_2\cdot 2H_{2}O+4H_{2}O$
The remaining two molecules of water are not removed but react chemically with $MgC{l}_2$ to form $MgO$.
$MgC{l}_2+2H_{2}O\to MgO+2HCl+H_{2}O$