Stoichiometry
The mass of 0.2 moles of a substance is 8.8g. What is the molar mass of the substance?
44 grams
What is the maximum number of electrons that can occupy a p-orbital?
2
Arrange the following metals in the correct order of metallic bond strength from strongest to weakest: Na, K, Rb, Mg
Mg>Na>K>Rb
How many dichlorinated butane isomers can be formed by the halogenation of CH3CH2CH2CH3 with excess Cl2 in the presence of UV light?
6
What is the mass of oxygen that is required to burn 460g of ethanol?
960g of O2
How many p-orbitals are occupied in a phosphorus atom?
6
What are the predicted electron domain geometries around the carbon and both nitrogen atoms in urea, (NH2)2CO, applying VSEPR theory?
Carbon - trigonal planar
Nitrogen - tetrahedral
Explain the difference between homolytic fission and hetrolytic fission of Cl2
Homolytic - electron are distributed equally between chlorine atoms: Cl2-->2Cl*
Hetrolytic - electron are distributed unequally between chlorine atoms: Cl2-->Cl-+Cl+
Metal X reacts with 16.0 g of sulfur to produce 26.0 g of the compound XS2. What is the relative atomic mass of X?
40
The full electron configuration of an element is: 1s22s22p63s23p2 To which group and period does the element belong?
group 14, period 3
Which compound has the shortest C to O bond?
A. CH3CHO
B. CO
C. CO2
D. C2H5OC2H5
B
What are the reagents and conditions to convert ethanol to ethanal?
oxidation agent (Cr2O7-2), and distillation
20 cm3 of gas A reacts with 20 cm3 of gas B to produce 10 cm3 of gas AxBy and 10 cm3 of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product AxBy (g)?
XY2
What are the products of a reaction between potassium and excess water?
KOH and H2(g).
Silicon and carbon are in the same group. Explain why is CO2 gas in room temperatuer while SiO2 is solid
CO2 - London dispersion attractions between the molecules
SiO2 - giant covalent structure
Which of the following species are nucleophiles?
H2O, CN-, OH-, NH3
all of them
What is the concentration of chloride ions, in mol dm−3, in a solution formed by mixing 200 cm3 of 1 mol dm−3 HCl with 200 cm3 of 2.5 mol dm−3 CaCl2?
3 mol dm−3
What is the correct order for increasing first ionization energy of Na, Mg, Al
Na < Al < Mg
(due to the electron in a higher sublevel p in Al)
Which process is reflects making of hydrogen bonds?
A. H* +H* --> H2(g)
B. H2O(l) --> H2O(g)
C. NH3(g) --> NH3(l)
D. 2H2(g) + O2(g) --> 2H2O(l)
C
What are the IUPAC names of the reagents required to synthesis the following substance: (CH3)3CO2CCH3
methylpropan-2-ol and ethanoic acid (and concentrated H2SO4)