Answer
a. $Ca(OH)_2$
b. $CaCrO_4$
c. $Ca_3(PO_4)_2$
d. $Ca(CN)_2$
Work Step by Step
Use table 3.4 (Page 100) and figure 3.7 (Page 98) to see the charges and the formula of the ions.
- Calcium has a charge of $2+$, and its symbol is $Ca$: $Ca^{2+}$
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a. Hydroxide ion is: $OH^-$ (See table 3.4).
Calcium: $Ca^{2+}$
Put these two together, where the subscript number will be the charge of the other ion. Calcium will receive 1, and hydroxide will receive 2.
$Ca_1(OH)_2$: $Ca(OH)_2$
b. Chromate ion is: $CrO_4^{2-}$ (See table 3.4).
Calcium: $Ca^{2+}$
Put these two together, where the subscript number will be the charge of the other ion. Calcium will receive 2, and chromate will receive 2.
$Ca_2(CrO_4)_2$: $CaCrO_4$
c. Phosphate ion is: $PO_4^{3-}$ (See table 3.4).
Calcium: $Ca^{2+}$
Put these two together, where the subscript number will be the charge of the other ion. Calcium will receive 3, and phosphate will receive 2.
$Ca_3(PO_4)_2$
c. Cyanide ion is: $CN^{-}$ (See table 3.4).
Calcium: $Ca^{2+}$
Put these two together, where the subscript number will be the charge of the other ion. Calcium will receive 1, and cyanide will receive 2.
$Ca_1(CN)_2$ : $Ca(CN)_2$
