Answer:
There are 342 g/ 95. 2 g/m = 3.59 moles
Explanation:
MgCl2 → Molar mass is 95.2g g/m
This is the mass in one mol so to find out the moles in 342g we have to divide the mass between the molar mass.
342 g/ 95. 2 g/m = 3.59 moles
<u>Answer:</u>
<u>For a:</u> The increasing of atomic radius is:
Al < Mg < Na
<u>For b:</u> The pH of the solution of sodium oxide is greater than 7.
<u>Explanation:</u>
Atomic radius is defined as the distance of the nucleus to the outermost shell containing electrons.
It decreases as we move from left to right in a period because electrons get added up in the same shell and effective nuclear charge increased which results in the shrinkage of the atom.
Sodium lies in Period 3, group 1. Its atomic radius is 1.90
Magnesium lies in Period 3, group 2. Its atomic radius is 1.60
Aluminium lies in Period 3, group 3. Its atomic radius is 1.32
The increasing of atomic radius will be:
Al < Mg < Na
The mathematical values proves the result.
There are 3 types of solution based on pH:
- If pH > 7, the solution is basic in nature.
- If pH < 7, the solution is acidic in nature.
- If pH = 7, the solution is neutral in nature.
When a metal reacts with oxygen present in air, it forms basic oxide which simply means when they react with water, they form basic solution.
The chemical equation for the reaction of sodium (metal) with oxygen present in air and reaction with water of the product so formed are as follows:
Sodium forms a basic solution when its oxide reacts with water, therefore the pH of the solution will be greater than 7.
Protons are positively charged and are found inside the nucleus of an atom
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Answer:
Explanation:
Total cards available = 8
Probability of drawing Blue = 5/8
Probability of drawing Yellow = 3/8
Step 1
Probability of drawing blue card first = 5/8.
Since, the first drawn blue card is NOT replaced; Total card available = 7
Then, probability of drawing blue card again = 4/7.
Finally, the probability of drawing TWO blue cards = 5/8 × 4/7
= 5/14.
So, the number belonging to the green box is 5.