Mass of strontium = 88 g
Atomic mass of Sr = 87.62 u
Moles = mass /atomic mass
Moles of Sr = 88 / 87.62 = 1.004
Mass of bromine = 160 g
Atomic mass of Br = 79.904 u
Molar mass of Br₂ = 79.904 x 2 = 159.808 g/mol
Moles = mass /molar mass
Moles of Br₂ = 160 / 159.808 = 1.001
The balanced chemical equation of the reaction between strontium and bromine:
Sr(s) + Br₂(l) = SrBr₂
The molar ratio between Br₂ and SrBr₂ is 1:1
So the moles of SrBr₂ produced from 1.001 moles of Br₂ is 1.001.
Moles = mass /molar mass
Mass = moles x molar mass
Molar mass of SrBr₂ = 247.4280 g/mol
Mass = 1.001 mol x 247.4280 g/mol
Mass = 247.428 g
The mass of strontium bromide produced is 247.428 g.
It depends if you are taking the class in high school or college. For college doing the experiments is fun but the calculations is not. Also if you are taking it, bring friends.
Answer: Option (d) is the correct answer.
Explanation:
Carbon tetrachloride
is a non-polar solvent. Whereas out of the given options,
,
,
, and HI are all polar molecules.
On the other hand, only
is non-polar molecule.
Also it is known that like dissolves like.
So, being non-polar
will dissolve the give alkane,
.
Answer: C.
Explanation: Alcohol floats on oil and water sinks in oil. Water, alcohol, and oil layer well because of their densities, but also because the oil layer does not dissolve in either liquid. The oil keeps the water and alcohol separated so that they do not dissolve in one another. ... Water sinks because it is more dense than oil.
Answer: b} The exact time when an individual atom will decay can be accurately predicted.
c} After each half-life, the amount of radioactive material is reduced by half.
Explanation:
All radioactive decay follows first order kinetics.
Rate law expression for first order kinetics is given by:
where,
k = rate constant
t = time taken for decay process
a = initial amount of the reactant
a - x = amount left after decay process
Expression for calculating half life, which is the time taken by the half of the reactants to decompose is:
