Question

ДОПИШИТЕ УРАВНЕНИЕ ХИМИЧЕСКИХ РЕАКЦИЙ РАСТАВТЕ КОЭФФИЦЕНТЫ .......+О2---CuO Al2 O3+ H2---.....+....... HCL+Mg --- ......+........ И ЗАДАЧА В РЕАКЦИЮ С КИСЛОРОДОМ ВСТУПИЛО 4Г КАЛЬЦИЯ ВЫЧИСЛИТЕ МАССУ ОБРОЗОВАВШЕГОСЯ ОКСИДА КАЛЬЦИЯ

Answer 1

2Cu + O2 --> 2CuO
2Al2O3 + 3H2 --> 4Al + 6H2O 

2HCl + Mg --> MgCl2 + H2

задача.
2Сa + O2 --> 2CaO
n(Ca) = m/M = 4г / 40 г/моль = 0,1 моль
n (CaO) = n (Ca) = 0,1 моль
m (CaO) = n * M = 0,1 моль * 56 г/моль = 5,6г 

Answer 2

Balancing Chemical Equations:

To balance the chemical equations you provided, we need to ensure that the number of atoms of each element is the same on both sides of the equation. Here are the balanced equations:

1. O2 → CuO: - The unbalanced equation is: O2 → CuO - To balance it, we need to add a coefficient of 2 in front of CuO: O2 → 2CuO [[1]].

2. Al2O3 + H2 → ...: - The unbalanced equation is: Al2O3 + H2 → ... - To balance it, we need to add a coefficient of 2 in front of Al2O3 and 3 in front of H2: 2Al2O3 + 3H2 → ... [[2]].

3. HCl + Mg → ...: - The unbalanced equation is: HCl + Mg → ... - To balance it, we need to add a coefficient of 2 in front of HCl and 1 in front of Mg: 2HCl + Mg → ... [[3]].

Calculating the Mass of Calcium Oxide:

To calculate the mass of calcium oxide formed when 4g of calcium reacts with oxygen, we need to determine the balanced equation for the reaction between calcium and oxygen.

The balanced equation for the reaction between calcium and oxygen is:

2Ca + O2 → 2CaO

From the balanced equation, we can see that 2 moles of calcium react with 1 mole of oxygen to produce 2 moles of calcium oxide.

To calculate the mass of calcium oxide formed, we need to use the molar mass of calcium oxide, which is 56.08 g/mol.

First, we need to calculate the number of moles of calcium:

moles of calcium = mass of calcium / molar mass of calcium

moles of calcium = 4g / 40.08 g/mol = 0.0998 mol

Since the balanced equation shows that 2 moles of calcium react to form 2 moles of calcium oxide, we can conclude that 0.0998 moles of calcium will produce 0.0998 moles of calcium oxide.

Finally, we can calculate the mass of calcium oxide formed:

mass of calcium oxide = moles of calcium oxide * molar mass of calcium oxide

mass of calcium oxide = 0.0998 mol * 56.08 g/mol = 5.59 g

Therefore, the mass of calcium oxide formed when 4g of calcium reacts with oxygen is approximately 5.59 grams.

I hope this helps! Let me know if you have any further questions.