Answer:
Cr(s) ⟶ Cr⁴⁺(aq) + 4e⁻
Explanation:
1. Write the skeleton half-reaction
Cr(s) ⟶ Cr⁴⁺(aq)
2. Balance charge
Add electrons to the side that needs them.
You have 4+ on the right and 0 on the left. You must add 4e⁻ to the right to balance the charge.
Cr(s) ⟶ Cr⁴⁺(aq) + 4e⁻
Explanation:
Are there any values given in the question?
Answer: There is one way to write it but i’ll also provide an unbalanced equation and a balanced one.
Explanation:
Unbalanced : Ba (aq) + Cl2 (aq)—-> BaCl (aq)
Balanced : 2Ba (aq) + Cl2 (aq)—> 2BaCl(aq)
Answer:
0.4 moles
Explanation:
To convert between moles and grams you need the molar mass of the compound. The molar mass of of CaCO3 is 100.09g/mol. You use that as the unit converter.
40gCaCO3* 1mol CaCO3/100.09gCaCO3 = 0.399640 mol CaCO3
This rounds to 0.4 moles CaCO3
