6- the chemical formula of carbonate salt contain monovalent cation is O XCO3
O X2HCO3
O X2CO3
O X(HCO3)2
7- after adding sodium hydroxide into hydrochloric acid, pH will
O Increases
O decreases
O remains constant
8- the reaction between calcium hydroxide and Nitric acid forming
o Ca(NO2)2
O Ca(NO3) O Ca(NO3)2
o Ca(NO2)

6-

because X has only one positive charge.

7-

because there is increase in hydroxyl ions which decrease the acidity or hydrogen strength of hydrochloric acid.

8-

Calcium has a valency of 2 and nitrate ion radicle has valency of 1

hey there!

mass = 6.75 g

volume =   9 cm³

therefore:

d = mass / volume

d   = 6.75 / 9

d = 0.7 g/cm³

answer b