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fdsfsdf 發問於 科學及數學化學 · 6 年前

# Chemistry

a) What carbonates, hydrogencarbonates, metal oxides, metal hydroxides are

soluble in water?

b) When writing ionic equations, can Mg(OH)2 be split into Mg ions and OH ions?

c)Is heat released in the reaction between metal and acid or acid with carbonates?

d) Write an ionic equation for the following experiment: Adding dilute hydrochloric acid to solid sodium hydrogencarbonate. (My concern is whether solid hydrogencarbonate can be split into different ions form)

### 1 個解答

• 6 年前
最愛解答

a)

carbonate: only potassium carbonate, sodium carbonate and ammonium carbonate is soluble in water. All other common carbonates are insoluble in water.

hydrogencarbonate: all hydrogencarbonates are soluble in water.

metal oxide and metal hydroxide are bases, bases of group I and group II elements are soluble in water. The special cases are Be and Mg. They can be considered as insoluble in water.

b)

Mg(OH)2 is insoluble in water, Therefore you can't seperately write Mg2+ and OH-. Instead, Mg(OH)2(s) is correct.

c)

Yes, these reactions are exothermic, they release more energy (in form of heat) than that they absorb.

d)

hydrogencarbonate + acid -> water + CO2 + salt

so the ionic equation is

NaHCO3(s) + H+(aq) -> CO2(g) + H2O(l)

NaHCO3 is in solid state, ions can't be written seperately.