Numerade guide dedicated to demystifying math. From basic arithmetic to advanced concepts, I help students navigate the numerical realm, instilling confidence and a love for the precision of math.
The compounds of boron and hydrogen are collectively called(a) Boranes(b) Boracits(c) Borazoles(d) Diboranes
The alum used for purifying water is(a) Chrome alum(b) Ammonium alum(c) Potash alum(d) Ferric alum
$\mathrm{BCl}_{3}$ is a planar molecule because in this molecule boron is(a) Sp ^{2} - \text { hybridised }(b) Sp-hybridised(c) Sp $^{3}$ -hybridised(d) Sp $^{3}$ d-hybridised
Heating an aqueous solution of aluminium chloride to dryness will give(a) $\mathrm{AlCl}_{3}$(b) $\mathrm{Al}_{2} \mathrm{Cl}_{3}$(c) $\mathrm{Al}(\mathrm{OH}) \mathrm{Cl}_{2}$(d) $\mathrm{Al}_{2} \mathrm{Cl}_{6}$
Boron nitride on reacting with caustic alkali gives(a) $\mathrm{NO}_{2}$(b) $\mathrm{N}_{2} \mathrm{O}$(c) $\mathrm{Na}_{2} \mathrm{BO}_{2}$(d) $\mathrm{NH}_{3}$
What mass of NH3 gas has a volume of 16,400 mL, a pressureof 0.955 atm and a temperature of -23 °C?
Electrons in a hydrogen atom fall from level 10 tolevel 8 . Calculate the energy required (in kJmol-1) to remove an electron from level 8.
If an organic molecule has three chiral centres, which of thefollowing is themaximum number of possible optical isomers?(a) 3(b) 12(c) 6(d) 8
Chlorine atoms recombine to form Cl2 according to a second-order rate law with a first half-life of 100 milliseconds and an initial chlorine atom concentration of 2.0x10^12 atoms/mL. What is the rate constant for this reaction?
Which of the following will give a positive chemical test withnitrous acid?(a) CH3CH2NH2(b) CH3CH2CHO(c) CH3CO2CH3(d) (CH3)3N
When two reactant molecules collide, they don’t always produceproduct. What two additional factors must besatisfied before a collision leads to product formation.
