Moles of calcium metal used = 100/40.1=2.5
Moles of HBr need to react = 5 moles
As the molar ratio is 1 is to 2 among them
so
Moles=molarity x volume
5=2.25 x volume
volume=2.22 litres of HBr required for this reaction
ANSWER IS 2.22 LITRES
<span> As we know that MgI2 (magnesium iodide) when dissociated it gives more ions than the KI so it has more boiling point as its boiling point is high it means that it boils more so it has low vapor pressure and freezing point
On the other hand as we know that KI dissociates into two ions so so it has high freezing and vapor pressure
hope it helps</span>
Answer: c. +4
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.




Here manganese is having an oxidation state of +4 called as cation and oxygen forms an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged to give
which written in simplest whole number ratios to give neutral 
Answer:
true. e.g
iron+water+oxygen->hydratedironoxide
There is 6 non - bonding pairs.
Let me show you one easy method to do this.
o22-, oxygen valence electron = 6 here we have two so total 12, and -2 that means we add electrons so it’s all equal to 14 right.
whenever need to find lone pair, subtract the number you get with the lowest multiple of 8.
here we total 14 valence electron right so lowest multiple of 8 would be 8.
so 14 - 8 = 6 and that is our answer.
Let me know if you have Problem with chemistry.