What are the answer choices?
Answer: The correct answer is in chemical bonds
Explanation:
When coal is burnt, these components burn and release energy. The energy released is by the chemical reaction between the constituents and oxygen
Answer:
False
Explanation:
False. The molecules of liquid are hold in the liquid state due to intermolecular forces or Van de Waals forces , without affecting the molecule itself and its atomic bonds (covalent bonds). When the temperature increases the kinetic energy of the molecules is higher , therefore they have more possibilities to escape from the attractive intermolecular forces and go to the gas state.
Note however that this is caused because the intermolecular forces are really weak compared to covalent bonds, therefore is easier to break the first one first and go to the gas state before any covalent bond breaks ( if it happens).
A temperature increase can increase vaporisation rate if any reaction is triggered that decomposes the liquid into more volatile compounds , but nevertheless, this effect is generally insignificant compared with the effect that temperature has in vaporisation due to Van der Waals forces.
Answer:
K⁺ (aq) + F⁻ (aq) + H⁺ (aq) + Cl⁻ (aq) → KCl (aq) + H⁺ (aq) + F⁻ (aq)
Explanation:
KF (aq) + HCl (aq) → KCl (aq) + HF (aq)
KF (aq) → K⁺ (aq) + F⁻ (aq)
HCl (aq) → H⁺ (aq) + Cl⁻ (aq)
KCl (aq) → K⁺ (aq) + Cl⁻ (aq)
HF (aq) → H⁺ (aq) + F⁻ (aq)
Answer:
A beam balance is an example of a first class lever.
Explanation:
A beam balance is an example of a first class lever. In a first class lever, the fulcrum is between the effort (force) and the load. The effort (force) moves over a large distance to move the load a smaller distance.
Other examples of first class lever are pliers, scissors, a crow bar, a claw hammer, a see-saw and a weighing balance etc.
