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Three orbital shapes, labelled I, II and III, are drawn below. Which row correctly identifies the shapes of a 2s orbital and a 2p orbital? A. 2s: II, 2p: I B. 2s: I, 2p: III C. 2s: I, 2p: II D. 2s: III, 2p: II
When 3.71 g of Z was burned completely in excess oxygen, 8.81 g of carbon dioxide and 4.51 g of water were collected. Determine the empirical formula of Z. Use sections 1 and 7 of the data booklet.
A second sample of Z was converted completely into vapour at a known temperature and pressure. (i) 0.148 g of the vapour occupied 63.7 cm3 at 110 °C and a pressure of 1.00 × 105 Pa. Calculate the amount, in mol, of Z in this sample. Use…
What is the empirical formula of a compound with the following composition by mass? A. C6HO4 B. C4H8O C. C2H4O D. C4H8O2
How many electrons, at most, can be held in the fifth main energy level (n = 5) of an atom? A. 10 B. 25 C. 32 D. 50
90.0 cm3 of buta-1,3-diene and 150.0 cm3 of hydrogen are mixed in a container at 450 K and 101 kPa and react to form butane only. Determine the maximum volume of butane that can be formed, measured at the same temperature and pressure.
Determine the total volume of gas present in the container at the end of the reaction described in 5a, under the same conditions of temperature and pressure.
A fixed amount of an ideal gas is kept at constant temperature while the volume of its container is decreased by 60 %. How does the pressure of the gas change? pV = nRT A. Pressure decreases by 60 % B. Pressure increases by 60 % C. Pressure increases by 150…
The displayed formula below shows part of the chain of an addition polymer. (i) Deduce the structural formula of the monomer used to build this polymer. (ii) Describe one chemical property responsible for this type of polymer being a useful material.
The compound X shown below occurs naturally in cocoa and coffee and is used as a flavouring agent. (i) State the name of the functional group found in compound X. (ii) Deduce the IUPAC name of X. (iii) Draw a structural isomer of X taken from a different…