The pollutant usually presents in a city which generates its electricity from coal?
fog
carbon(ii)oxide
smog
sulphur(iv)oxide
Correct answer is D
In the majority of power plants, sulfur appears due to coal burning which is used to generate electricity.
The reactions below represent neutralization reaction, in which of them is the value of ΔH highest?
CH\(_3\)CH\(_2\)COOH + KOH → CH\(_3\)CH\(_2\)COOK + H\(_2\)O
NH\(_4\)OH + HCL → NH\(_4\) + H\(_2\)O
NaOH + HCL → NaCL + H\(_2\)O
CH\(_3\)COOH + NaOH → CH\(_3\)COONa + H\(_2\)O
Correct answer is C
The enthalpy change of neutralisation involving weak acids are smaller in magnitude compared to that between strong acids and strong bases. This is because weak acids/bases are partially dissociated, which means not all hydrogen ions are free to react with hydroxide ions.
For strong acids and bases, the enthalpy of neutralisation values are always closely similar with the values -57 and -58 KJ/mol. We know that strong acids completely ionize in water. In case of weak acids, only partial dissociation of its ions occurs.
31.6
62.2
32.7
31.1
Correct answer is D
Charles' law is a special case of the ideal gas law in which the pressure of a gas is constant.
Charles's law defines the direct relationship between temperature and volume.
GIVEN DATA: V\(_1\) = 29.5cm\(^3\), V\(_2\) = ? , T\(_1\) = 0ºc or 273k, T\(_2\) = 15ºc or 288k
\(\frac{V_1}{T_1}\) = \(\frac{V_2}{T_2}\)
V\(_2\) = \(\frac{V_1 x T_2}{T_1}\) → \(\frac{29.5 x 288}{273}\)
V\(_2\) = 31.1cm\(^3\)
In which of the following will hydrogen form ionic compound?
HCL
NaH
NH\(_3\)
CH\(_4\)
Correct answer is B
NaH is a saline (salt-like) hydride, composed of Na+ and H− ions
85cm\(^3\)
50cm\(^3\)
125cm\(^3\)
55cm\(^3\)
Correct answer is B
Since 2 mol H\(_2\) reacted with 1 mol of O\(_2\)
: 50cm\(^3\) of hydrogen reacted with 25cm\(^3\) of oxygen
Remainder oxygen = Supplied amount - Reacted amount → 75cm\(^3\) - 25cm\(^3\)
= 50cm\(^3\)