4.) D
10.) C
12.) D
13.) D
14.) D
15.) D
Answer:
b) 2.0 mol
Explanation:
Given data:
Number of moles of Ca needed = ?
Number of moles of water present = 4.0 mol
Solution:
Chemical equation:
Ca + 2H₂O → Ca(OH)₂ + H₂
now we will compare the moles of Ca and H₂O .
H₂O : Ca
2 : 1
4.0 : 1/2×4.0 = 2.0 mol
Thus, 2 moles of Ca are needed.
False, because water vapor, water vapour or aqueous vapor, is the gaseous phase of water. It is one state of water within the hydrosphere. Water vapor can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Unlike other forms of water, water vapor is invisible.
Explanation:
21. The given molecule for cracking is tetradecane.
On cracking it forms one mole of decane (C10H22) and two moles of ethene gas.
The chemical equation is shown below:

22. The essential condition for the formation of an ester is the reaction of alcohol and acid in presence of concentrated sulfuric acid.
Thus among the given options, the first option is the correct one.
23. Isomers of butanol are shown below:
It is 2-butanol.
The position of -OH group changes to the second carbon.
Answer:
Answer B
Explanation:
By definition mixtures are combinations of substances physically prepared and physically separated. Mixtures are classified as 'homogeneous mixtures' and 'heterogeneous mixtures'. For homogeneous mixtures all components are dissolved, with solute evenly distributed throughout the solution and assumes state of solvent. 'Heterogeneous mixtures' have inconsistent properties throughout and solute concentration is not consistent throughout the mixture.