W = AB x F x Cos < AB, F
or just W= AB x F for short
Answer:
The answer is: (a) positive; (b) negative.
Explanation:
The change in enthalpy (ΔH) of a reaction is the amount of energy absorbed or released during a chemical reaction carried out at constant pressure.
a) In an endothermic chemical reaction, heat energy is absorbed by the system from the surrounding. Therefore, the sign of enthalpy change for an endothermic process is positive, ΔH= positive.
b) In an exothermic chemical reaction, heat energy is released by the system into the surrounding. Therefore, the sign of enthalpy change for an exothermic process is negative, ΔH= negative.
<h3>
Answer:</h3>
A. 860 kg
<h3>
Explanation:</h3>
To answer the question we need to understand that;
- Mass refers to the amount of matter in an object.
- Weight, on the other hand, refers to the gravitational pull of an object to a given surface.
- Mass is measured using a spring balance.
We also need to know that;
- The mass of an object remains constant every where irrespective of the gravitational acceleration.
- Therefore, an object on the surface of the earth would have the same mass as on the surface of the moon.
- In this case; the mass of the car remains the same on the outer space as on the back yard.
