On the basis of the given unbalanced equation, that is:
HBr (aq) + 2NaOH (aq) → 2NaBr (s) + H2O (l)
On the right side of the equation, there are 2 atoms of sodium (Na), 2 atoms of bromine (Br), 2 atoms of hydrogen (H), and 1 atom of oxygen (O₂).
After balancing the equation correctly we get:
HBr (aq) + NaOH (aq) → NaBr (s) + H2O (l)
On the right side, one atom of Na, 1 atom of Br, 1 atom of H and one atom of O₂.
b. Polar covalent bonds. The polar N-H bonds hold the NH3 molecules together. They are <em>intramolecular forces</em> of attraction <em>within a molecule</em>.
All the other options are <em>wrong</em>. They are <em>intermolecular forces</em> — the attractive forces <em>between different molecules</em>.
The answer c) A- Cell membrane because it selects what molecules enter/exit the cell
1kg is 1,000 grams plus .5 is 1.5 kg