Answer:
Boiling water breaks intermolecular attractions and electrolysis breaks covalent bonds.
Explanation:
When water boils, hydrogen bonds are broken between adjacent water molecules. The hydrogen bond is an intermolecular bond between adjacent oxygen and hydrogen atoms of water molecules.
During electrolysis, water dissociates in the presence of electric current. Here, ions are formed in the process. Therefore, covalent bonds are broken here.
Answer:
The correct answer is
B.

Explanation:
Enthalpy of reaction :
It is the amount of energy released/absorbed when one mole of the substance is formed from the reactant at a constant pressure.
The enthalpy of a reaction can be calculated using :









Please note that :
The carbon monoxide , CO should be taken as C triple bond O. Not C=O .
So , the bond energy =1072 is used

Answer is: 2. atomic number.
Atomic number is unique and defines an element. Atomic number (Z) is total number of protons in an atom.
For example, nitrogen atom (N-14) has 7 protons (p⁺), 7 electrons (e⁻) and 7 neutrons (n°). Protons (positive charge) and neutrons are in the nucleus of atom, electrons (negative charge) are bound to the nucleus in spherical shells. Nitrogen is an element with atomic number 7. Mass number (A) is the total number of protons and neutrons in a nucleus. Nitrogen mass number is 14 (A = p⁺ + n°; A = 14).
Answer:
C. If a solar cell breaks, it releases chemicals and can harm humans.
Explanation:
Hope this helped! :)