Hydrogen have only one electron and easily form compounds with other elements that is the reason hydrogen is chemically unstable
Answer: C is the correct answer
Explanation:
To completely describe an electron in an atom, four quantum numbers are needed: energy (n), angular momentum (ℓ), magnetic moment (mℓ), and spin (ms).
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Answer:
0.027 mole of NaOH.
Explanation:
We'll begin by obtaining the number of mole H2SeO4 in 45mL of 0.30M H2SeO4
This is illustrated below:
Molarity of H2SeO4 = 0.3M
Volume of solution = 45mL = 45/1000 = 0.045L
Mole of H2SeO4 =...?
Mole = Molarity x Volume
Mole of H2SeO4 = 0.3 x 0.045
Mole of H2SeO4 = 0.0135 mole
Next, the balanced equation for the reaction. This is given below:
H2SeO4 + 2NaOH –> Na2SeO4 + 2H2O
From the balanced equation above,
1 mole of H2SeO4 required 2 moles of NaOH.
Therefore, 0.0135 mole of H2SeO4 will require = 0.0135 x 2 = 0.027 mole of NaOH.
Therefore, 0.027 mole of NaOH is needed for the reaction.
Reaction equation:
Zn + 2HCl → ZnCl₂ + H₂
One mole of gas occupies 22.4 L at STP
Moles of H₂ = 112/22.4
= 5 moles
The theoretical amount of Zn needed is 5 mol
The actual amount = 5/0.85
= 5.88 moles
mass = moles x Mr
mass = 5.88 x 65
mass = 382.2 g
The answer is D.