Answer:
Change in volume on changing temperature from 33
to 5 is 5.49 mL
Explanation:
Initial volume of gas = V = 60 mL
Assuming final volume of gas to be V' mL
Initial temperature = T = 33 = 306 K
Final temperature = T' = 5 = 278 K
The relationship between volume and temperature of gas at constant pressure is shown below
Change in volume on changing temperature = 5.49 mL
Answer: exothermic
EXPLANATION: any process in which heat energy is released is called an exothermic process. For example burning of wood produces heat, so combustion of wood is an exothermic process.
When chemicals were not mixed they were at room temperature and when we mix them exothermic reaction took place and heat was released which raised the temperature of mixture.
In a combustion reaction, one of the reactants is always oxygen.
Answer:
a solution color becoming less intense due to dilution- is not an evidence of a chemical reaction
bubbles (gas formation) - evidence of a chemical reaction
explosion or fire - evidence of a chemical reaction
changes in color- evidence of a chemical reaction
precipitation- evidence of a chemical reaction
changes in temperature - evidence of a chemical reaction
a solid liquifying - is not an evidence of a chemical reaction
solution colors mixing - is not an evidence of a chemical reaction
Explanation:
A chemical change is not easily reversible and yields new substances. It is often accompanied by a loss or gain of heat.
In the answer section, i have shown some evidences that lead us to conclude that a chemical reaction has taken place. The occurrence of a chemical change often goes with the formation of new substances as earlier stated and any of these signs may accompany the process.
For instance, when a metal is dropped in dilute acid solution, bubble of hydrogen gas indicates that a chemical reaction has taken place.
Well it’s the first answer couches
