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Which condition out of the following will increase the evaporation of water?

Adding common salt to waterLess exposed surface area of waterDecrease in temperature of waterIncrease in temperature of water

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In which of the following conditions, the distance between the molecules of hydrogen gas would increase?
(i) Increasing pressure on hydrogen contained in a closed container
(ii) Some hydrogen gas leaking out of the container
(iii) Increasing the volume of the container of hydrogen gas
(iv) Adding more hydrogen gas to the container without increasing the volume of the container

(ii) and (iv)(ii) and (iii)(i) and (iv)(i) and (iii)

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Two chemical species X and Y combine together to form a product P which contains both X and Y
X + Y → P
X and Y cannot be broken down into simpler substances by simple chemical
reactions. Which of the following concerning the species X, Y and P are correct?
(i) P is a compound
(ii) X and Y are compounds
(iii) X and Y are elements
(iv) P has a fixed composition

(i), (iii) and (iv)(ii), (iii) and (iv)(i), (ii) and (iv)(i), (ii) and (iii)

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3.42 g of sucrose are dissolved in 18g of water in a beaker. The number of oxygen atoms in the solution are

6.022 × 10²¹6.022 × 10²³6.09 × 10²²6.68 × 10²³

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A change in the physical state can be brought about

without any energy changewhen energy is either given to, or taken out from the systemonly when energy is taken out from the systemonly when energy is given to the system