Answer:
The energy change in a chemical reaction is due to the difference in the amounts of stored chemical energy between the products and the reactants. This stored chemical energy, or heat content, of the system is known as its enthalpy.
Explanation:
Due to the absorption of energy when chemical bonds are broken, and the release of energy when chemical bonds are formed, chemical reactions almost always involve a change in energy between products and reactants. By the Law of Conservation of Energy, however, we know that the total energy of a system must remain unchanged, and that oftentimes a chemical reaction will absorb or release energy in the form of heat, light, or both.
Answer:
→A space heater warms a room⇒By converting electrical energy into heat energy.
→You eat dinner⇒Our body uses chemical energy to break down the food
→A radio plays⇒By converting electrical energy into sound energy in an electric radio. And by converting chemical energy into sound energy in a radio which runs with a cell.
Explanation:
Answer:
180 mg
Explanation:
For a first-order reaction, we can calculate the amount of aspirine (A) at a certain time (t) using the following expression.

where,
k: rate constant
A₀: initial amount
If we know the half-life (
) we can calculate the rate constant.

When t = 4 h and A₀ = 400 mg, A is:

Answer:
Chimia ne poate ajuta să înțelegem, monitorizăm, protejăm și îmbunătățim mediul din jurul nostru. Chimiștii dezvoltă instrumente și tehnici pentru a ne asigura că putem vedea și măsura poluarea aerului și a apei.
Explanation: I speak english i just know Romanian language
Answer: An african or a european swallow?