Answer:
Explanation:
H+ is a representation of the number if hydrogen ions also known as acidity of a substance, it is well known that pH <7 represents acidity and acidity increases from 6 to 0. 7 i known as neutral, while 8-14 represents alkalinity/base. pH scale ranges from 0-14. pH 10, 7, 5 is the order of increasing H+.
1) Answer: A hot pack feels warm when chemicals in it combine.
Explanation: Reactions or process in which heat is released(produced) are known as exothermic reactions or process and those in which the heat is absorbed are known as endothermic reactions or process.
If a beaker feels cools when chemical in it react then it means the chemicals have absorbed the heat energy from its surroundings and so it is an example of an endothermic process.
A hot pack feels warm when chemicals in it combine means the energy is released in the chemical reaction and so it is an example of an exothermic process.
Plants use the sun's energy for photosynthesis which is a process of forming food for the plants. Energy acts as a reactant in this process and so it is an example of endothermic process.
Frying an egg by heating it on a stove is an example of an endothermic process as the heat is required to fry the egg.
So, the only exothermic process is the second one, "A hot pack feels warm when chemicals in it combine."
2) In the given equation, heat is written as a product means the heat is released in the equation and so it is an example of an exothermic reaction.
So, the correct choice is the last one " It is exothermic because energy is released."
Answer:
Here, we are required to determine the total energy of the reaction and determine if the reaction is an endothermic or exothermic reaction.
The correct answer is option C.
First, we need to determine the energy of the reaction.
The energy of the reaction is the change in enthalpy between the product and reactants.
Change of Enthalpy,
Hreaction = Hproduct - Hreactant.
Therefore, for the reaction above, the change in enthalpy is:
Hreaction = 590kJ/mol - 581kJ/mol.
Hreaction = 9kJ/mol.
Hence, since the reaction has an enthalpy change of 9kJ/mol, the reaction is endothermic (i.e energy is absorbed).
Explanation:
Answer: Volume – How much space an object or substance takes up. Mass – Measurement of the amount of matter in an object or substance.
Explanation:
Answer:
31.7 °C
Explanation:
Charles law states that for volume of a gas is directly proportional to the absolute temperature for a fixed amount of gas at constant pressure
we can use the following equation
V1/T1 = V2/T2
where V1 is volume and T1 is temperature at first instance
V2 is volume and T2 is temperature at second instance
temperature should be in kelvin scale
T1 - 0 °C + 273 = 273 K
substituting the values in the equation
22.4 L / 273 K = 25.0 L / T2
T2 = 304.7 K
temperature in celcius is - 304.7 K - 273 = 31.7 °C
the gas must be 31.7 °C to reach a volume of 25.0 L
