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प्रश्न
What type of ions are formed?
When a base (or alkali) is dissolved in water.
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उत्तर
When a base is dissolved in water, it always produces hydroxide (OH−) ions.
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संबंधित प्रश्न
Name one natural source of the following acid:
Oxalic acid
When a piece of limestone reacts with dilute HCl, a gas X is produced. When gas X is passed through lime water then a white precipitate Y is formed. On passing excess of gas X, the white precipitate dissolves forming a soluble compound Z.
- What are X, Y and Z?
- Write equations for the reactions which take place:
- When limestone reacts with dilute HCl.
- When gas X reacts with lime water to form white precipitate Y.
- When excess of gas X dissolves white precipitate Y to form a soluble compound Z.
Why is it wrong to treat a wasp sting with baking soda solution?
Write the neutralisation reaction between acids and bases in terms of the ions involved.
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\[\ce{Acid + Active metal -> Salt + hydrogen}\]
Write balanced equation to satisfy the following statement:
\[\ce{Acid + sulphide -> Salt + Hydrogen sulphide}\]
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Give the name and formula of two : Non-volatile acids
Complete the following table and write one equation for each to justify the statement:
|
Reactants |
Products |
Method |
|
Soluble base + Acid (dil) |
Salt + water |
Neutralisation Titration |
|
Metal + Non-metal |
Salt (soluble/insoluble) |
______ |
|
Insoluble base + ______ |
Salt (soluble) + water |
______ |
|
Active metal + Acid (dil) |
______ + ______ |
______ |
|
Soluble salt solution (A) + Soluble salt solution (B) |
Precipitated salt + Soluble salt |
______ |
|
Carbonate/bicarbonate + Acid (dil) |
Salt + ______ + ______ |
Decomposition of carbonate |
|
Chlorides/nitrates + Acid (conc.) |
______ + ______ |
Decomposition of chlorides and nitrates |
Answer the following question.
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Fill in the cross word given in figure with the help of the clues provided.
Across
(2) The solution which does not change the colour of either red or blue litmus.
(4) Phenolphthalein gives pink colour in this type of solution.
(7) Colour of blue litmus in lemon juice.
Down
(1) It is used to test whether a substance is acidic or basic.
(3) It is a natural indicator and gives pink colour in basic solution.
(5) Nature of ant’s sting.
(6) It is responsible for the increase in temperature during a neutralisation reaction.
Complete the following equation.
Zn + ______ → Na2ZnO2 + H2 ↑
Complete the following equation.
CaO + H2SO4 → ______ + H2O
A metal 'M' on reacting with dilute acid liberates a gas 'G'. The same metal also liberates gas 'G' when reacts with a base.
- Write the name of gas 'G'.
- How will you test the presence of this gas?
- Write chemical equations for the reactions of the metal with (1) an acid and (2) a base.
Explain the following:
\[\ce{H3PO3}\] is not a tribasic acid.
