I think we're in the same class lol
1. Sodium
2. Gold
3. Helium
4. Sulfur
5. Magnesium
6. Cesium.
7. Silicon
8. fluorine
9. Nickel
10. Magnesium
11. Tungsten
12. hydrogen
13. Calcium
I did my best, here's my answers. Enjoy.
b) The reactivity of alkali metals increases as atomic mass increases.
Answer:200/3 M which is approximately equal to 66.6667 M
Explanation:Molarity is defined as the number of moles of solute per liter of solution.
It can be calculated as follows:

We are given that:
number of moles of solute = 8 moles
volume of solution = 120 ml = 0.12 liters
Substitute with the givens in the above equation to get the molarity as follows:
molarity =

Hope this helps :)
Answer:
The answer would be Point of Reference.
In order to determine, whether an object has moved or not, a point of reference is required. The reference point is required to the measure the movement of the object, without a reference point the distance or displacement cannot be obtained. Hence, a reference point is very required to determine, whether the object has moved or not.
(Hope this helps) Sky
Answer:
Na
Explanation:
because sodium has 1 electrons so it loses it to be stable and so have positive charge of 1