1) reactants: Ca + O2 (g)
2) Unbalanced equation: Ca + O2 (g) -> CaO
3) Balanced equation: 2Ca + O2 (g) -> 2CaO
Answer:
The answer to your question is below
Explanation:
Trial 1 Trial 2
mass of Mg 0.255 g 0.353 g
mass of MgO 0.418 g 0.576 g
Chemical reaction
2Mg(s) + O₂(g) ⇒ 2MgO(s)
Question 1.
Atomic mass of Mg = 24.31 x 2 = 48.62 g
Molecular mass of MgO = 2(24.31 + 16) = 80.62 g
Trial 1
48.62 g of Mg ----------------- 80.62 g of MgO
0.255 g ---------------- x
x = (0.255 x 80.62)/48.62
x = 0.422 g of MgO
Trial 2 48.62 g of Mg ----------------- 80.62 g of MgO
0.353 g ---------------- x
x = (0.353 x 80.62)/48.62
x = 0.585 g of MgO
Question 2
Trial 1
Percent yield = 0.418/0.422 x 100 = 99%
Trial 2
Percent yield = 0.576/0.585 x 100 = 98.5%
Question 3
Average = (99 + 98.5)/2
= 98.75%
Answer : The volume of gas will be, 113.5 L
Explanation :
Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.
The combined gas equation is,

where,
= initial pressure of gas = 60 atm
= final pressure of gas = 30 atm
= initial volume of gas = 29 L
= final volume of gas = ?
= initial temperature of gas = 115 K
= final temperature of gas = 225 K
Now put all the given values in the above equation, we get:


Therefore, the volume of gas will be, 113.5 L
Answer:
C ; Use enough cations and anions so that the total charge is zero
in a stable ionic compound, in order for you to get the formula, you need the positive and negative ions on one side to cancel out the compound, it becomes neutral, by being 0.
i hope that made sense :/