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प्रश्न
The elements whose oxides can turn litmus solution red are:
(a) lithium and sodium
(b) copper and potassium
(c) carbon and hydrogen
(d) phosphorus and sulphur
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उत्तर
(d) phosphorus and sulphur
Phosphorus and sulphur are non-metals whose oxides are acidic in nature. These oxides turn blue litmus solution to red.
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संबंधित प्रश्न
‘E’ is an element which reacts with oxygen to form an oxide E2O. An aqueous solution of E2O turns red litmus blue, so:
i. What is the nature of oxide E2O ?
ii. Write the name of element ‘E’.
You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.
The reaction of an iron nail with copper sulphate solution is ........... reaction.
(a) Combination
(b) Displacement
(c) Double displacement
(d) Decomposition
A solution of _________________ in water is green in colour.
(a) CuSO4
(b) FeSO4
(c) ZnSO4
(d) Al2(SO4)3
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Fill in the following blank with suitable word:
The white powder formed when magnesium ribbon burns in oxygen is of ....................
Fill in the following blank with suitable word:
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The elements whose oxides can turn phenolphthalein solution pink are:
(a) Na and K
(b) K and C
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(a) CO
(b) H2O
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The metals which can produce amphoteric oxides are:
(a) sodium and aluminium
(b) zinc and potassium
(c) calcium and sodium
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Write the chemical equation for the following reaction:
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