Answer:
13.94moles of Na₂O
Explanation:
The balanced reaction expression is given as:
4Na + O₂ → 2Na₂O
Given parameters:
Number of moles of O₂ = 6.97moles
Unknown:
Number of moles of Na₂O
Solution:
To solve this problem;
1 mole of O₂ will produce 2 moles of Na₂O ;
6.97 moles of O₂ will produce 6.97 x 2 = 13.94moles of Na₂O
Answer:
Strontium
Explanation:
The atomic number of strontium is 38.
It has 38 electrons.
It is alkaline earth metal. It has two valance electrons.
Strontium loses its two electrons and form cation with +2 charge.
Electronic configuration;
Sr₃₈ = [Kr] 5s²
The valance electrons present in 5s are lost by strontium atom and form Sr⁺² cation.
it is yellowish-white metal.
It is highly reactive.
It form salt with halogens.e.g
Sr + Br₂ → SrBr₂
IT react with oxygen and form oxide.
2Sr + O₂ → 2SrO
this oxide form hydroxide when react with water,
SrO + H₂O → Sr(OH)₂
With nitrogen it produced nitride,
3Sr + N₂ → Sr₃N₂
With acid like HCl,
Sr + 2HCl → SrCl₂ + H₂
They can all by seperrated or replicated.
Answer:
1)Krypton
2)11H
Explanation:
electrons=protons
protons=atomic number
mass number=protons+neutrons
mass number is the superscript
atomic number is the subscript.
1)The answer is Krypton because its atomic number= number of protons=number of electrons is 36.
mass number is 46+36=82.
2)subscript=atomic number=number of protons=number of electrons
i. H = electrons=1
=neutrons=0
ii. Cl=electrons=17
=neutrons=35-17=18
iii. Na=electrons=11
=neutrons=23-11= 12
so the answer is Hydrogen because it has 1 electron and 0 neutron.
I hope this helps.
