Chemical change, because the white powder heated the water and caused a thermal reaction, and possibly gas was produced due to bubbles.
Salt water is a Homogeneous Mixture......
Answer:
x² = mutiphy by them self
Explanation:
In a solution of KBr and water; KBr is the solute and water is the solvent;
Therefore; to achieve 3% by mass; it means we are going to have 3% of the mass being the solute and the other 97 % being the solvent.
Thus; KBr (solute) = 3/100 × 300 (total mass) = 9 g
Hence; the appropriate masses will be; 9.00 g of KBr and 291 g of water.
Answer:

Explanation:
Hello there!
In this case, by bearing to to mind the given conditions, it is firstly possible to determine the initial volume of the closed system via the ideal gas equation:

Which is V1 in the Charles' law:

And of course, T1 is 298.15 (25+273.15). Therefore, by solving for V2 as the final volume, we obtain:

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