3.0x10-4..............................
Answer: HCl
Explanation:
calcium carbonate dissolves in HCl acid producing CO 2 gas. It will not dissolve in pure water. The Ksp for calcium carbonate in water is 3.4 x 10-9 moldm-3 which is very low. What takes place here is actually a chemical reaction:
CaCO 3 (s) + 2HCl(aq) → CaCl 2 (aq) + H 2CO 3(aq)
This reaction accounts for the solubility of the Calcium carbonate in HCl and not in pure water.
Pressure does not affect the voltage produced in a voltaic cell.
Answer:
- <em><u>Option A. </u></em><u><em>2KClO₃ → 2KCl + 3O₂</em></u>
Explanation:
There are five basic general types of chemical reactions:
- Synthesis or combination reaction
- Single replacement reactions
- Double replacement reactions
The given reactions are:
- <u>2KClO₃ → 2KCl + 3O₂</u>
Which is, indeed, a decomposition reaction because the reactant, KClO₃, is a single substance that undergoes a reaction in which it yields two new substances, known as products: KCl and O₂.
- <u>4Na + O₂ → 2Na₂O</u> is a synthesis or combination reaction because two reactants, Na and O₂, combine for the formation of one single new product, Na₂O.
- <u>ZnS + 3 O₂ → 2ZnO + 2SO₂ </u>is a single replacement reaction because oxygen is replacing Zn and S in ZnS to form ZnO and plus SO₂.
- <u>2NaBr + CaF₂ → 2NaF + CaBr₂ </u>is a double replacement reaction because two ions (Br⁻ from NaBr and F⁻ from CaF₂) are exchanging places with other two ions (Na⁺ from NaBr and Ca²⁺ from CaF₂) two form two new ionic compounds (NaF and CaBr₂).
