Answer:
D) burning a candle
A demonstration that contains both physical and chemical changes will be BURNING OF A CANDLE.
<em>This is because when a candle is lighted up, on the top of it (where we see flame) the oxygen and other gases present around will be chemically changed (burned up)</em>
<em>When the wax in the top of the candle will get melted due to the heat of the fire a physical change takes places.</em>
Answer:
The perceived mass of CO2 would not be affected in large quantities because the splash constitutes small particles of water with sodium bicarbonate that is still reacting. The final calculated mass of sodium bicarbonate in the tablet would be artificially low.
Explanation:
Effervescence is a chemical process that involves the reaction of an acid with a carbonate or sodium bicarbonate, releasing carbon dioxide through a liquid. An example is seen in carbonated beverages, in these the gas that escapes from the liquid is carbon dioxide. The bubbles that are seen are produced by the effervescence of the dissolved gas, which by itself is not visible in its dissolved form.
Answer: 0.011 moles.
Explanation:-
To calculate the moles, we use the equation:
Given :
Mass of copper = 0.71 g
Molar mass of copper = 63.5 g/mol
Putting i the values, we get:
Thus the number of moles of copper in 0.71 g of copper is 0.011 moles.
-ideal gas: a hypothetical gas whose molecules exhibit no interaction and undergo elastic collision with each other and the walls of the container
-macroscopic properties: properties that can be visualized or measured by the naked eye; examples include pressure, temperature, and volume
