Answer:
13.4mol of Mg
Explanation:
Given parameters:
Mass of magnesium = 321g
Unknown:
Number of moles = ?
Solution:
The number of moles of a substance is given as;
Number of moles = 
Molar mass of Mg = 24g/mol
Insert the parameters and solve;
Number of moles = 
= 13.4mol of Mg
Answer:
Alkaline earth metals
Explanation:
Group 2 has 2 valence electrons that they lose when being ionized, thus making their charge 2+.
1) Chemical equation
Na2 SiO3 (s) + 8 HF (aq) ---> H2 Si F6 (aq) + 2 Na F (aq) + 3H2O (l)
It is balanced
2) Molar ratios
1 mol Na2 SiO3 : 8 mol HF.
3) Proportion
0.340 mol Na2 SiO3 * 8 mol HF / 1mol Na2SiO3 = 2.72 mol HF.
Answer: 2.72 mol HF
I believe it might be A. Damaged buildings.
B is a positive and so is Tourism.
The kinetic energy and the physical state of water depend strongly on the temperature;
- Firstly, The kinetic energy of water on a hot stove is higher than that on the counter in the freezer; that the kinetic energy is directly proportional to the temperature according to the relation:
; where R is the universal gas constant, T is the temperature and NA is Avogadro number.
As the temperature increases, the speed of colliding molecules increases and the kinetic energy increases.
- Secondly, The physical state of water depends on the temperature; water has three states (gas, liquid and solid) depends on the temperature.
- If a glass of water is putt on the counter in the freezer, it will be converted to the solid state (ice).
- And, as if it is putt on a hot stove, it will be vapor (gaseous state).
