If you do not wait until the crucible is at room temperature, its density will vary constantly until it reaches this temperature, since density is a property that varies with temperature. For the above reason, weighing a hot crucible will not allow the measurement of a constant weight on the balance, since <u>the weight of the object will be constantly changing, which will not allow a constant reading.</u>
If it's the liquid inside:
mercury
I think the answer would be d but not 100% sure
<span>2 NH</span>₃<span> + 3 O</span>₂<span> + 2 CH</span>₄<span> </span>⇒<span> 2 HCN + 6 H</span>₂<span>O
2mol : 2mol
34g : 54g
25,1g : x
x = (25,1g * 54g) / 34g </span>≈ 39,9g<span>
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