Two element X and Y form compounds X 2 Y 3 and XY 2 O 3 (when combined with O 2 ). If 0.15 mole of X 2 Y 3 weighs 15.9 gm and 0.15 mole of XY 2 O 3 weighs 16.5 gm find the atomic wei

Question

Two element X and Y form compounds X 2 ​ Y 3 ​ and XY 2 ​ O 3 ​ (when combined with O 2 ​ ). If 0.15 mole of X 2 ​ Y 3 ​ weighs 15.9 gm and 0.15 mole of XY 2 ​ O 3 ​ weighs 16.5 gm find the atomic weights of X & Y . Represents your answer as abcd, where "ab" represent atomic weight of X and "cd" represent atomic weight of Y. Suppose your answer is 24 & 9 then the same must be filled in as 2409

TestHub · Accepted Answer

To find the atomic weights of X and Y, we set up a system of equations based on the given information.

For compound $X_{2} Y_{3}$ :

Molar mass of $X_{2} Y_{3} = \frac{ma ss}{m o l es} = \frac{15.9 g m}{0.15 m o l} = 106 g m / m o l$

So, $2 X + 3 Y = 106$ (Equation 1)

For compound $X Y_{2} O_{3}$ :

Molar mass of $X Y_{2} O_{3} = \frac{ma ss}{m o l es} = \frac{16.5 g m}{0.15 m o l} = 110 g m / m o l$

The atomic weight of Oxygen (O) is 16 gm/mol.

So, $X + 2 Y + 3 (16) = 110$

$X + 2 Y + 48 = 110$

$X + 2 Y = 110 - 48$

$X + 2 Y = 62$ (Equation 2)

Now we solve the system of equations:

1) $2 X + 3 Y = 106$

2) $X + 2 Y = 62$

Multiply Equation 2 by 2:

$2 (X + 2 Y) = 2 (62)$

$2 X + 4 Y = 124$ (Equation 3)

Subtract Equation 1 from Equation 3:

$(2 X + 4 Y) - (2 X + 3 Y) = 124 - 106$

$Y = 18$

Substitute $Y = 18$ into Equation 2:

$X + 2 (18) = 62$

$X + 36 = 62$

$X = 62 - 36$

$X = 26$

The atomic weight of X is 26 and the atomic weight of Y is 18.

As per the instruction, the answer should be represented as "abcd", where "ab" is the atomic weight of X and "cd" is the atomic weight of Y.

So, the answer is 2618.

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