<u>Answer:</u> Electrons are taken up by
and they are lost by 
<u>Explanation:</u>
Redox reaction is defined as the reaction in which oxidation and reduction take place simultaneously. It is also called the reaction where the exchange of electrons takes place.
An oxidation reaction is defined as the reaction in which a chemical species loses electrons takes place. In this reaction, the oxidation state of a substance gets increased.
A reduction reaction is defined as the reaction in which a chemical species gains electrons takes place. In this reaction, the oxidation state of a substance gets reduced.
For the given chemical reaction:

The half-reactions for this redox rection follows:
<u>Oxidation half-reaction:</u> 
<u>Reduction half-reaction:</u> 
Hence, electrons are taken up by
and they are lost by 
<u>Answer:</u> The mass of solid NaOH required is 80 g
<u>Explanation:</u>
Equivalent weight is calculated by dividing the molecular weight by n factor. The equation used is:

where,
n = acidity for bases = 1 (For NaOH)
Molar mass of NaOH = 40 g/mol
Putting values in above equation, we get:

Normality is defined as the umber of gram equivalents dissolved per liter of the solution.
Mathematically,

Or,
......(1)
We are given:
Given mass of NaOH = ?
Equivalent mass of NaOH = 40 g/eq
Volume of solution = 400 mL
Normality of solution = 5 eq/L
Putting values in equation 1, we get:

Hence, the mass of solid NaOH required is 80 g
Explanation:
Al2O3
16=molar mass of one oxygen atom
Number of moles: mass/molar mass
Mol of O3: 19÷(16*3) = 0.40 g/mol
mole ratio
0.40: 3 (oxygen)
0.27: 2 (aluminum)
Mass = molar mass*mole
0.27*(27*3)= 21.87g
Answer: increasing number of protons increases the positive charge of the nucleus.
Explanation: because as the electronegativity moves from left to right on the periodic table the protons do increase to make it into a positive charge.