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(A) Name the acid present in ant sting and give its chemical formula. Give the common method to get relief from the pain and irritation caused by ant sting.
(B) Two solutions 'X' and 'Y' have pH values 3.0 and 9.5 respectively.
Which of these will turn blue litmus to red and which will turn phenolphthalein from colourless to pink ?
(B) Two solutions 'X' and 'Y' have pH values 3.0 and 9.5 respectively.
Which of these will turn blue litmus to red and which will turn phenolphthalein from colourless to pink ?
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(A)
$\bullet$ Formic acid / Methanoic acid ($\frac{1}{2}$ Mark)
$\bullet$ $\ce{H-C-OH / HCOOH}$ ($\frac{1}{2}$ Mark)
$\bullet$ Rubbing the affected area with a mild base like baking soda gives relief. / any other suitable method. (1 Mark)
(B)
$\bullet$ X will turn blue litmus red (as it is acidic) ($\frac{1}{2}$ Mark)
$\bullet$ Y will turn phenolphthalein pink (as it is basic) ($\frac{1}{2}$ Mark) (Reason is optional)
$\bullet$ Formic acid / Methanoic acid ($\frac{1}{2}$ Mark)
$\bullet$ $\ce{H-C-OH / HCOOH}$ ($\frac{1}{2}$ Mark)
$\bullet$ Rubbing the affected area with a mild base like baking soda gives relief. / any other suitable method. (1 Mark)
(B)
$\bullet$ X will turn blue litmus red (as it is acidic) ($\frac{1}{2}$ Mark)
$\bullet$ Y will turn phenolphthalein pink (as it is basic) ($\frac{1}{2}$ Mark) (Reason is optional)