Answer:
A- beryllium
B- calcium
C- magnesium
Explanation
NOTE: all element in group 2 have 2 balance electrons
First let’s start with B- number of electrons= number of protons which is equal to the atomic number. therefore, the answer is calcium as it’s atomic number is 20
C- magnesium will have three energy levels considering it has 12 electrons (2,8,2).
A- beryllium is the lightest one in group 2 as it has the atomic mass of 9.0122.
<span>Some of them remained in space, some ended up in the gas giants, Jupiter, Saturn, etc. A good percentage ended up in the sun</span>
Answer:
Alkali metal hydroxides can be used to test the identity of metals in certain salts. The colour of the precipitate will help identify the metal : Calcium hydroxide is soluble; no precipitate is formed.
Answer:
-) Oxidizing agent: 
-) Reducing agent: 
Explanation:
The first step is separate the reaction into the <u>semireactions</u>:
A.
B.
If we want to balance in <u>basic medium </u>we have to follow the rules:
1. We adjust the oxygen with 
2. We adjust the H with 
3. We adjust the charge with 
Lets balance the first semireaction A. :
Now, lets balance semireaction B:
Finally, we have to add the two semireactions:
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Cancel out the species on both sides:
Simplifying the equation :
The is <u>oxidized</u> therefefore is the <u>reducing agent</u>. The is<u> reduced</u> therefore is the <u>oxidizing agent</u>.
