The volume of $0.1 \ M \ HCl$ required in $mL$ to neutralise $20 \ mL$ of a solution containing $0.106 \ g$ of $Na_2CO_3$ is

The yield of each step as actually carried out in the laboratory is given in the reaction scheme below. Calculate the overall percentage yield of the reaction.
$Me_3C-CO-CH_3$ $\xrightarrow{58\% (A)} Me_3C-CO-CH_2Br$ $\xrightarrow{54\% (B)} Me_3C-CH(OH)-CH_2Br$ $\xrightarrow{68\% (C)} Me_3C-CH(O)CH_2$

Suppose a cooking gas cylinder contains $11.2 \, kg$ of isobutane. The thermochemical equation for the combustion of butane is given below:
$C_4H_{10}(g) + \frac{13}{2} O_2(g) \to 4CO_2(g) + 5H_2O(\ell); \Delta H = -2658 \, kJ$
If a family requires $15000 \, kJ$ of energy per day for cooking,how many days will the cylinder last?

$Elodea$ is an aquatic plant that performs photosynthesis in water. The photosynthesis reaction is given by: $6CO_{2(g)} + 6H_2O_{(l)} \to C_6H_{12}O_{6(aq)} + 6O_{2(g)}$. Calculate the mass of $CO_2$ in $g$ required to produce $112 \, mL$ of oxygen at $STP$.

How much $MgO$ is produced from $1.2 \ g$ of $Mg$ (atomic mass $= 24$)?

$510 \ mg$ of a liquid on vaporisation in Victor Mayer's apparatus displaces $510 \ cm^3$ of dry air (at $NTP$). The molecular weight of the liquid is: