2019 - JAMB Chemistry Past Questions and Answers - page 6
What volume of 0.100M sodium trioxonitrate (V) solution contains 5g of solute.
[Na = 23, N = 14, O = 16]
The two ions responsible for hardness in water are
Which of the following could not be alkane?
The electronic configuration of element Z is 1s\(^2\) 2s\(^2\) 2p\(^6\) 3s\(^2\) 3p\(^1\). What is the formula of the compound formed between Z and tetraoxosulphate (VI) ion.
Z\(_3\)(SO\(_4\))\(_2\)
ZSO\(_4\)
Z\(_2\) SO\(_4\)
Z\(_2\)(SO\(_4\))\(_3\)
Z = 1s\(^2\) 2s\(^2\) 2p\(^6\) 3s\(^2\) 3p\(^1\)
\(\therefore\) We have Z\(^{3+}\) and SO\(_4 ^{2-}\)
The formula is:
Z\(^{3+}\) + SO\(_4 ^{2-}\) \(\to\) Z\(_2\)(SO\(_4\))\(_3\).
The hybridization in the compound \(CH_3 - CH_2 - C \equiv H\) is
The hybridization in a and b is sp\(^3\) hybridization while in c and d is sp hybridization.
The following are isoelectronic ions except
Na\(^+\)
Mg\(^{2+}\)
Si\(^{2+}\)
O\(^{2+}\)
Isoelectronic refers to two atoms, ions, or molecules that have the same electronic structure and the same number of valence electrons. Atoms or ions with the same electronic configurations are said to be isoelectronic to each other or to have the same isoelectronicity
Na\(^+\) = 10 electrons = 2, 8
Mg\(^{2+}\) = 10 electrons = 2,8
O\(^{2-}\) = 10 electrons = 2,8
Si\(^{2+}\) = 12 electrons = 2,8,2
\(\implies\) Si\(^{2+}\) is not isoelectronic with the rest.
Consider the reaction: A + 2B\(_{(g)} \rightleftharpoons \) 2C + D\(_{(g)}\) (\(\Delta\)H = +ve)
What will be the effect of decrease in temperature on the reaction?
Rate of backward reaction will increase
The equilibrium constant will shift
Rates of forward and backward reactions are not affected
Rate of forward reaction will increase
The given reaction is endothermic, as a result of that, a decrease in temperature will favour the exothermic side which is the backward reaction.
A cell shorthand notation can be written as A / A\(^+\) // B\(^{2+}\) /B. The double slash in the notation represents the
The shapes of water, ammonia, carbon (iv) oxide and methane are respectively
Which quantum divides shells into orbitals?
Spin
Principal
Azimuthal
Magnetic
An azimuthal quantum number is a quantum number for an atomic orbital that determines its orbital angular momentum and describes the shape of the orbital. It is also known as the orbital angular momentum quantum number, orbital quantum number or second quantum number, and is symbolized as ℓ (pronounced ell).