The answer is 33.33 %
The explanation:
According to the reaction equation:
MgCO3(s) + 2HCl (aq) --> MgCl2(aq) + H20(l) + CO2(g)
we can see that 1 mole of MCO3 will produce → 1 mole of CO2
-Now we need o get number of mole of CO2:
and when we have 0.22 g of CO2, so number of mole = mass / molar mass
moles = 0.22 g / 44 g/mol = 0.005 mole
∴ moles of Mg = moles of CO2 = 0.005 mole
∴ mass of Mg = moles * molar mass
= 0.005 * 84 /mol = 0.42 g
∴ Percent of MgCO3 by mass of Mg = 0.42 g / 1.26 * 100
= 33.33 %
Answer:
the correct answer is option C. Na
C, it prevents the Earth from ultraviolet radiation and other harmful substances from space
<span>Chemists considered Martian
Periodic Table as one of the most useful tools they’ve used whose purpose is to
arrange the Martian elements according
to their properties and their atomic number. On this periodic table, it was
found out that the properties seem to vary.
Dmitri Mendeleev, the first to arrange the periodic table according to
atomic mass in a manner that the elements with the same properties were grouped
together. It was Henry Moseley who later arranged the periodic table in accord
to the increasing number of atoms per element. </span>