the answer is a chemical element
Answer:
The half life is 
Explanation:
The half life of a first order reaction is mathematically represented as
Substituting
for the rate constant

Answer:
<u>Mass concentration (g/L) </u><u><em>= 2.49g/L.</em></u>
Explanation:
No. of moles = 
=
= 0.001245 moles
Concentration of KHP (C1) in litres = n/v
=
= 0.062 mol/L
We know that:
=
where c1v1 and c2v2 are the products of concentration and volumes of KHP and NaOH respectively.
Since mole ratio is 1 : 1.
1 mole of NaOH - 40g
0.001245 mole of NaOH = 40 × 0.001245 = 0.0498g
⇒0.0498g of NaOH was used during the titration
<u><em>∴Mass concentration (g/L) = 0.0498g ÷ 0.02L</em></u>
<u><em>= 2.49g/L.</em></u>
2 moles of sodium hydroxide will be needed.
<h3><u>Explanation</u>:</h3>
Sodium hydroxide is a compound which is a base and nitric acid is the acid. The formula of the nitric acid is HNO3 and that of sodium hydroxide is NaOH.
The reaction between them are
NaOH +HNO3 =NaNO3 +H2O.
So here we can see that 1 mole of sodium hydroxide reacts with 1 mole of nitric acid to produce 1 mole of sodium nitrate and 1 mole of water.
So for 2 moles of nitric acid, 2 moles of sodium hydroxide will be required.
Answer:
- Option A): <em>Due to the constraints upton the angular momentum quantum number, the subshell </em><u><em>2d</em></u><em> does not exist.</em>
Explanation:
The <em>angular momentum quantum number</em>, identified with the letter l (lowercase L), number is the second quantum number.
This number identifies the shape of the orbital or <em>kind of subshell</em>.
The possible values of the angular momentum quantum number, l, are constrained by the value of the principal quantum number n: l can take values from 0 to n - 1.
So, you can use this guide:
Principal quantum Angular momentum Shape of the orbital
number, n quantum number, l
1 0 s
2 0, 1 s, p
3 0, 1, 2 s, p, d
Hence,
- <u>the subshell 2d (n = 2, l = 2) is not feasible</u>.
- 2s (option B) is possible: n = 2, l = 0
- 2p (option C) is possible: n = 2, l = 1