Self Studies

Hydrogen Test - 20

Result Self Studies

Hydrogen Test - 20
  • Score

    -

    out of -
  • Rank

    -

    out of -
TIME Taken - -
Self Studies

SHARING IS CARING

If our Website helped you a little, then kindly spread our voice using Social Networks. Spread our word to your readers, friends, teachers, students & all those close ones who deserve to know what you know now.

Self Studies Self Studies
Weekly Quiz Competition
  • Question 1
    1 / -0
    $$3.4$$ g of $$H_{2}O_{2}$$ decomposes, the weight of oxygen liberated from it is:
    Solution
    $$2{ H }_{ 2 }{ O }_{ 2 } \rightarrow 2{ H }_{ 2 }O +{ O }_{ 2 }$$.
    $$68$$ g of $${ H }_{ 2 }{ O }_{ 2 }$$ produce --- $$32$$ g of $${ O }_{ 2 }$$
    $$3.4$$ g of $${ H }_{ 2 }{ O }_{ 2 }$$ produce --- $$\dfrac { 32 }{ 68 } \times 3.4 = 1.6$$ g of $${ O }_{ 2 }$$.
  • Question 2
    1 / -0
    The volume of perhydrol which on decomposition gives 1.5 lit of $$O_{2}$$ gas at STP is:
    Solution
    As, it is a perhydrol sample, $$1$$ ml of $$H_{2}O_{2}$$ would give $$100$$ ml of $$O_{2}$$ at room temperature. Thus, $$1.5$$ L of $$O_{2}$$ would be given by $$15$$ ml of $$H_{2}O_{2}$$.
  • Question 3
    1 / -0
    The volume strength of $$15\%$$ (w/v) solution of $$H_{2}O_{2}$$ is :
    Solution
    The solution is $$15\% (w/v)$$. It means $$100 \ ml$$ of solution contains $$15$$ g of hydrogen peroxide.
    The concentration in g/L is $$\dfrac {15}{100} \times 1000 =150 g/L$$.
    The relationship between the concentration in g/L and the volume strength $$\text{x}$$ is
    Conc. in g/L $$= \dfrac {680\times \text{(x)}}{224} g/L$$

    Thus, $$150 = \dfrac {680\times \text{(x)}}{224}$$
    $$\text{x}=50$$. Thus, the volume strength of solution is $$50$$.
  • Question 4
    1 / -0
    The volume of $$20\:V-H_{2}O_{2}$$ solution, required to prepare $$5$$ litres of oxygen at STP is:
    Solution
    $$20$$ ml of $${ O }_{ 2 }$$ is prepared by $$1$$ ml of $${ H }_{ 2 }{ O }_{ 2 }$$ at STP.

    $$1$$ ml of $${ O }_{ 2 }$$ is prepared by $$= \dfrac{1}{20}$$ ml of $${ H }_{ 2 }{ O }_{ 2 }$$.

    $$5000$$ ml of $${ O }_{ 2 }$$ is prepared by = $$\dfrac { 1 }{ 20 } \times 5000 = 250$$ ml of $${ H }_{ 2 }{ O }_{ 2 }$$.

    Hence, option B is correct.
  • Question 5
    1 / -0
    The volume (in ml) of oxygen liberated at STP when $$100$$ ml of $$15\:V$$ $$H_{2}O_{2}$$ decomposes is:
    Solution
    $$1$$ ml $$H_2O_2$$ of $$15$$ vol liberates $$15$$ ml of $$O_2$$ at STP.
    Hence, $$100$$ ml $$H_2O_2$$ of $$15$$ vol liberates $$15\times100$$ ml of $$O_2$$ at STP or $$1500$$ ml of $$O_2$$ at STP.
    Hence, option D is the correct answer.
  • Question 6
    1 / -0
    The volume strength of $$3N\:H_{2}O_{2}$$ solution is:
    Solution
    $$3\:N$$ means $$3$$ g eqwt. in $$1$$ L solution. 

    $$N=\dfrac{\text{weight}}{\text{eq. wt.}}$$.

    $$($$eq. wt. for hydrogen peroxide$$ = 17$$ g$$)$$ 

    Therefore, $$3 = \dfrac{\text{wt}}{17}$$ or $$\text{wt} = 3 \times17 = 51$$ g.

    Now, from the equation, we know that $$68$$ g of $$H_2O_2$$ gives $$22.4$$ L of Oxygen. 

    Therefore, $$51$$ g of hydrogen peroxide gives $$22.4 \times \dfrac{51}{68} = 16.8$$ L.

    Thus, volume strength is $$16.8$$ L, because volume strength is the volume of oxygen at STP given by one volume sample of hydrogen peroxide on heating.
  • Question 7
    1 / -0
    The $$\%$$ by weight of hydrogen in $$H_{2}O_{2}$$ is :
    Solution
    The molecular weight of $$H_2O_2$$ is $$34$$ g.
    It has $$2$$ g of $$H_2$$ in it.
    Therefore, percentage weight of $$H_2$$ $$=$$ $$\dfrac{2}{34}\times100 = 5.88\%$$
    Hence, the percentage weight of hydrogen in $$H_2O_2$$ is $$5.88\%$$.
  • Question 8
    1 / -0
    $$H_{2}O_{2}$$ turns blackened lead paintings to white colour. In this reaction it oxidizes $$PbS$$ to $$PbSO_{4}$$. The number of moles of $$H_{2}O_{2}$$ needed to oxidize $$0.1$$ moles of $$PbS$$ is:
    Solution
    The balanced equation is:

    $$PbS+4H_{2}O_{2}\rightarrow PbSO_{4}+4H_{2}O$$.

    The stiochiometric coefficient  of $$PbS$$ is $$1 $$ while that of $$H_{2}O_{2}$$ is $$4$$ in the balanced reaction.

    So, 0.1 mol will be oxidised by 0.4 mol of $$H_2O_2$$
  • Question 9
    1 / -0
    The co-ordination number of $$Na$$ in solid $$NaH$$ is:
    Solution
    Coordination number of $$Na$$ in $$NaH$$ is $$6$$ as its shape is octahedral.
  • Question 10
    1 / -0
    The reaction between $$H_2O_2$$ and $$KMnO_4$$ is $$2KMnO_4+3H_2SO_4+5H_2O_2 \rightarrow K_2SO_4+2MnSO_4+8H_2O+5O_2$$. 
    In a reaction excess of $$H_2O_2$$ is added to 0.1 mole of acidified $$KMnO_4$$ solution. Then the STP volume of $$O_2$$ liberated is:
    Solution
    $$0.1$$ mole of $$KMnO_{4}$$ produces $$0.25$$ moles of $$O_{2}$$ which has a volume of 22.4 x 0.25 litres at STP.
Self Studies
User
Question Analysis
  • Correct -

  • Wrong -

  • Skipped -

My Perfomance
  • Score

    -

    out of -
  • Rank

    -

    out of -
Re-Attempt Weekly Quiz Competition
Self Studies Get latest Exam Updates
& Study Material Alerts!
No, Thanks
Self Studies
Click on Allow to receive notifications
Allow Notification
Self Studies
Self Studies Self Studies
To enable notifications follow this 2 steps:
  • First Click on Secure Icon Self Studies
  • Second click on the toggle icon
Allow Notification
Get latest Exam Updates & FREE Study Material Alerts!
Self Studies ×
Open Now