Tag: acids and alkalis

Quizzes (2) Questions (32)

Questions Related to acids and alkalis

Multiple choice chemistry acids and alkalis acids with carbonates reactions of acids and bases properties of acids and bases

$ 2H _3PO _4 + 3Na _2CO _3 \rightarrow $
What are the products formed?

  1. $2NaPO _4 + 3H _2O + 3CO _2$
  2. $2Na _3PO _4 + 3H _2O + 3CO _2$
  3. $2Na _3PO _4 + H _2O + 3CO _2$
  4. $2Na _3PO _3 + 3H _2O + 3CO _2$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

On adding a carbonate to an acid, effervescence from carbon dioxide gas is released along with the formation of water and salt. $CO _2$ turns lime water milky.
Phosphoric acid + sodium carbonate $\rightarrow$ sodium phosphate + water + carbon dioxide
$ 2H _3PO _4 + 3Na _2CO _3 \rightarrow 2Na _3PO _4 + 3H _2O + 3CO _2 $

Multiple choice chemistry acids and alkalis acids with carbonates reactions of acids and bases properties of acids and bases

A solution reacts with crushed egg-shells to give a gas that turns lime-water milky. The solution contains:

  1. $NaCl$
  2. $HCl$
  3. $LiCl$
  4. $KCl$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Crushed egg shell has composition $CaCO _3$ reacts with acid and gives gas $CO _2$ which turns lime water $(Ca(OH) _2)$ milky by producing $CaCO _3$ again. The acid in given options is $HCl$. 

$CaCO _3 + 2HCl \rightarrow CaCl _2 + CO _2 + H _2O $
$Ca(OH) _2 + CO _2 \rightarrow CaCO _3 + H _2O$

Multiple choice chemistry acids and alkalis acids with carbonates reactions of acids and bases properties of acids and bases

Which of the following represents the products obtained when, $HCl$ reacts with sodium hydrogen carbonate?

  1. $NaCl$, $H _2O$ and $CO _2$
  2. $NaCl$ and $CO _2$
  3. $NaOH$ and $CO _2$
  4. $NaOH$, $H _2O $ and $CO _2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When $HCl$ reacts with sodium hydrogen carbonate, the products obtained are $NaCl,$ $H _2O$ and $CO _2$.
$\displaystyle NaHCO _3 + HCl \rightarrow NaCl + H _2O + CO _2$

Multiple choice chemistry acids and alkalis acids with carbonates reactions of acids and bases properties of acids and bases

Which of the following represents the products obtained when $HCl$ reacts with calcium carbonate?

  1. $CaCl _2$, $H _2O$ and $CO _2$
  2. $CaCl _2$ and $CO _2$
  3. $Ca(OH) _2$ and $CO _2$
  4. $Ca(OH) _2$, $H _2O $ and $CO _2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When $HCl$ reacts with calcium carbonate, the products obtained are $CaCl _2$, $H _2O$ and $CO _2$.
$\displaystyle CaCO _3 + 2HCl \rightarrow CaCl _2 + H _2O + CO _2$

Multiple choice chemistry acids and alkalis acids with carbonates reactions of acids and bases properties of acids and bases

When an acid reacts with a metal carbonate or metal hydrogen carbonate, it gives the corresponding salt, gas and product. Name the gas and product?

  1. Carbon dioxide, Water

  2. Carbon dioxide, Salt

  3. Hydrogen, Salt

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Acid + Metal carbonate  $\longrightarrow$ Salt + Water + Carbon dioxide

CaCO$ _3$ (calcium carbonate-metal carbonate) + 2HCl $\longrightarrow$ CaCl$ _2$ (calcium chloride-salt) + H$ _2$O + CO$ _2$

Multiple choice chemistry acids and alkalis neutralisations in everyday life acids and bases in daily life neutralisation reaction

Basic soil can be corrected by adding:

  1. urea

  2. nitric acid

  3. organic manure

  4. formic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Plants can neither grow in too acidic conditions nor grow in too basic conditions. Thus for the proper growth of the plant optimum pH of the soil has to be maintained.


If the soil is too basic then it can be corrected by using organic manure. Compost micro-organisms operate best under neutral to acidic conditions with their pH ranging from 5.8 to 8. 


Thus they not only help in maintaining the pH of the soil but also increase the nutrient availability and improve the quality of the soil (unlike inorganic chemical fertilizers which damage the soil quality). 

Thus organic manure creates acidic conditions, which help in neutralizing the basic soil and makes the pH optimum for plant growth.

Hence, the correct answer is the option (C).

Multiple choice chemistry acids and alkalis neutralisations in everyday life acids and bases in daily life neutralisation reaction

A 26 ml of $ N-Na _{2}CO _{3} $ solution is neutralized by the solutions of acids A and B in different experiments. The volumes of the acids A and B required were $10 ml$ and $40 ml$, respectively. How many volumes of A and B are to be mixed in order to prepare 1 litre of normal acid solution? 

  1. $179.4, 820.6$
  2. $820.6, 179.4$
  3. $500, 500$
  4. $474.3, 525.7$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

$ N _{1}V _{1} (Na _{2}CO _{3}) = N _{2}V _{2} (A)$
$ N _{1}V _{1} (Na _{2}CO _{3}) = N _{2}V _{2}(B)$
$ N _{1} = 1 , V _{1} = 26ml, V _{2} = 10ml, V _{3} = 40ml$
Normality of A
$ N _{2} = \dfrac{N _{1}V _{1}}{V _{2}} = \dfrac{1 \times 26}{10} = 2.6 N $
Normality of B
$ N _{3}= \dfrac{N _{1}V _{1}}{V _{3}} = \dfrac{1 \times 26}{40} = 0.65 N $
if we mix A & B then
$ N _{1}V _{1} + N _{2} V _{2} = N _{3} (V _{1}+V _{2})$
$ 2.6 V _{1}+0.65V _{2} = 1 \times 1000 $
$ 2.6V _{1}+ V _{2} + 0.65 V _{2} = 1000 ...(1)$
$ V _{1}+V _{2} =1000 ...(2)$
multiply $eq^{n}$ (2) by 0.65 
$ 0.65 V _{1}+0.65V _{2} = 650 ...(3)$
$ V _{2} = 820.6 ml$
$ V _{1} = 1000 - 820.6 = 179.4 ml $
option "a" correct.

Multiple choice chemistry acids and alkalis neutralisations in everyday life acids and bases in daily life neutralisation reaction

What volume of $ 0.18 N - KMnO _{4} $ solution would be needed for complete reaction with 25 ml of $ 0.21 N - KNO _{2} $ in acidic medium ?

  1. $57.29 ml$
  2. $11.67 ml$
  3. $29.17 ml$
  4. $22.92 ml$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$ KMnO _{4}+KNO _{2}$
$ 0.18 N $ 25 ml
V = ? 0.21 N
we know $ N _{1}V _{1}= N _{2}V _{2}$
$ 0.18 \times V _{1} = 0.21 \times 25 $
$ V _{1} = \dfrac{0.21 \times 25}{0.18 }$
$ \boxed{V _{1} = 29.17 ml}$
Answer option C