<u>Answer:</u> The electronic configuration of gallium is written below and number of valence electrons is 3.
<u>Explanation:</u>
Electronic configuration is defined as the representation of electrons around the nucleus of an atom.
Number of electrons in an atom is determined by the atomic number of that atom.
Valence electrons are defined as the electrons present in the outermost shell of an atom.
We are given:
An element Gallium having atomic number as 31.
Number of electrons = 31
Electronic configuration of Gallium is: 
This element has 3 electrons in its outermost shell. So, the number of valence electrons is 3
Hence, the electronic configuration of gallium is written below and number of valence electrons is 3.
I believe it’s because they are trying to find other things that won’t pollute the environment as much, and they are also doing this because we are trying to reduce green house gas. Sorry if i’m wrong :(
Answer:
+4
Explanation:
In PbO2, oxygen exhibits an oxidation number of -2 (since it's not a peroxide or superoxide):
Let the oxidation number of Pb be x. Then, for the compound to be neutral, the oxidation numbers of all atoms should add up to zero.
⇒ x + (−2) + (−2) = 0
x = +4
So the oxidation no. of Pb is +4.
I hope this helps.
Answer:
Mass = 65.8 g
Explanation:
Given data:
Mass of sodium chloride = ?
Volume of solution = 1.5 L
Molarity of solution = 0.75 M
Solution:
Number of moles of sodium chloride:
Molarity = number of moles / volume in L
By putting values,
0.75 M = number of moles = 1.5 L
Number of moles = 0.75 M × 1.5 L
Number of moles = 1.125 mol
Mass of sodium chloride:
Mass = number of moles × molar mass
Mass = 1.125 mol × 58.5 g/mol
Mass = 65.8 g