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A mixture of compounds X and Y is analysed by thin layer chromatography. The stationary phase is silica gel and the solvent used is hexane. The chromatogram is shown. Which option is consistent with this chromatogram? A. RF of Y is 0.80; compound Y…
Which species contains a coordination bond? A. BCl3 B. PH3 C. [NH4]+ D. HCOO−
Which electrostatic attraction holds the two atoms together in a molecule of hydrogen, H2? A. Between the two nuclei B. Between the two electrons of the shared pair C. Between neighbouring hydrogen molecules D. Between each nucleus and the shared pair…
Asparagine, an amino acid, has the structure shown. What are the numbers of sigma (σ) and pi (π) bonds in one molecule of asparagine? A. 14 σ and 2 π B. 16 σ and 4 π C. 16 σ and 2 π D. 18 σ and 2 π
Which molecules are polar? I. CHCl3 II. CH2F2 III. CF4 A. I and II only B. I and III only C. II and III only D. I, II and III
Which molecule has a central atom with an expanded octet? A. ClF3 B. NF3 C. CF4 D. BeCl2
A section of the chain of an addition polymer is drawn below. From which monomer is this polymer made? A. CH2=CHCH2CH3 B. CH3CH2CH2CH3 C. CH3CH=CHCH3 D. (CH3)2C=CH2
How many sigma and pi bonds are present in pent-1-yne, C5H8? A. 12 sigma bonds and 2 pi bonds B. 8 sigma bonds and 3 pi bonds C. 13 sigma bonds and 1 pi bond D. 9 sigma bonds and 4 pi bonds
Which pair of compounds could react together in a condensation reaction that produces water? A. CH3CH2CH3 and Cl2 B. CH3CH=CH2 and HBr C. CH3CH2Cl and NH3 D. CH3CH2COOH and CH3CH2CH2OH
A segment of a condensation polymer is shown. Which statement is correct about one of the monomers from which this polymer is made? A. It is H2N(CH2)6NH2 B. It is H2N(CH2)4NH2 C. It is HOOC(CH2)6COOH D. It is H2N(CH2)5COOH