Which are the important ingredients present in Portland cement?

The solubility of sulfates in water decreases down the group for $Be$ to $Ba$. The correct order is $BeSO_4 > MgSO_4 > CaSO_4 > SrSO_4 > BaSO_4$. The reason for this is:

Given below are two statements:
Statement $I$: Both $CaCl_2 \cdot 6H_2O$ and $MgCl_2 \cdot 8H_2O$ undergo dehydration on heating.
Statement $II$: $BeO$ is amphoteric whereas the oxides of other elements in the same group are acidic.
In the light of the above statements,choose the correct answer from the options given below:

Among the following,which is water insoluble?

Which of the following components of cement is present in the highest amount?

Choose the correct statements from the following:
$(I)$ In vapour phase $BeCl_2$ exists as a chlorobridged dimer.
$(II)$ $BeSO_4$ is readily soluble in water.
$(III)$ $BeO$ is completely basic in nature.
$(IV)$ $BeCO_3$ being unstable, is kept in an atmosphere of $CO_2$.
$(V)$ $BeCO_3$ is the least soluble among all the carbonates of group $2$ elements.