Answer:
Mass = 15.1 g
Explanation:
Given data:
Number of moles of NaBH₄ = 0.40 mol
Mass in gram = ?
Solution:
Formula:
Mass = number of moles × molar mass
Molar mass of NaBH₄ = 37.83 g/mol
By putting values,
Mass = 0.40 mol × 37.83 g/mol
Mass = 15.1 g
Answer:
an acid is a substance which produces hydrogen ions as the only as the only positive ion when dissolved in water.
The compound crystallizes in the aluminium trifluoride motif. Each fluoride is a doubly bridging ligand. The cobalt centers are octahedral.
CoF3 decomposes upon contact with water to give oxygen:
4 CoF3 + 2 H2O → 4 HF + 4 CoF2 + O2
It reacts with fluoride salts to give the anion [CoF6]3−, which is also features high-spin, octahedral cobalt(III) center.
1) Balanced chemical reaction: Cl₂ + 2NaI → 2NaCl + I₂.
Chlorine and iodine are diatomic molecules.
2) Balanced chemical reaction: 2NH₃ → N₂ + 3H₂.
Nitrogen and hydrogen are diatomic molecules.
3) Balanced chemical reaction: 4Na + O₂ → 2Na₂O.
Sodium in compounds has oxidation number +1 and oxygen -2.
Equation for Half life :
A = a(0.5)^(t/h)
A is current amount, "a" is initial amount, h is halflife, t is time
5 = 40(0.5)^(t/1.3x10^9)
5/40 = (0.5)^(t/1.3x10^9)
take the log of both sides , power rule
Log(5/40) = (t/1.3x10^9) * Log(0.5)
(1.3x10^9) * Log(5/40) / Log(0.5) = t
3.9x10^9 years = t
And if you think about what a half life is, the time it take for the amount to reduce to half.
40/2 = 20
20/2 = 10
10/2 = 5
It went through 3 half-lifes
3 * 1.3x10^9 = 3.9x10^9 years
