Answer:
Explanation:
Hello,
In this case, since the percent abundance of Br-79 is 51.1% and that of the Br-81 is 48.9 %, we can write:
Taking into account that the mass of bromine from the periodic table is 79.909 amu, the mass of Br-81 turns out:
Best regards.
2 8 8 7 . 2 electrons in the K shell 8 elections in the L shell another 8 electrons in the M shell and finally 7 electrons in the N shell. manganese has 25 electrons
Answer:
Hi nisha is a good time for a good time to come
I am Real hearted and I am very excited about this opportunity and I am very excited about this place and I am very excited about this opportunity and I am very excited about this opportunity and I am very excited about this opportunity and I am very excited about this
Answer:
a) element
b) compound
c) element
d) compound
Explanation:
a) Hydrogen is the chemical element with the symbol H; is the lightest element in the periodic table.
b) Water: It is a substance whose molecule is composed of two atoms of hydrogen and one of oxygen.
⇒ molecular formula: H2O
c) gold: is the chemical element with the symbol Au. It is a very dense, soft and intense yellow metal.
d) sugar: it is a compound whose chemical formula is C12H22O11
3H₂ + N₂ → 2NH₃
mole of N₂ = mass ÷ molar mass
= 2.70g ÷ (14 × 2)
= 0.096 mol
mole ratio of N₂ : H₂
1 : 3
∴ if the moles of N₂ = 0.096 mol
then the mole of H₂ = 0.096 mol × 3
= 0.289 mol
Now, mass = mole × molar mass
∴ mass of H₂ needed to react = 0.289 mol × (1 × 2)
= 0.579 g