Answer:
Explanation:
(a) Answer: Intermolecular forces
The reason for this answer is because the substance (paraffin wax) only changed it's state from solid to liquid and didn't undergo a breakage in it's covalent bond within it's carbon chain which would have produced another substance.
(b) Solid substances are generally more dense than there corresponding liquid substances because the more compact particles are (which occurs in solids), the more dense they become. They are thus more dense than liquids because liquids have there particles loosely packed and well spaced making them less dense than there corresponding solids. Hence, the solid paraffin wax was going to become less dense because it's particles moved from being tightly packed (as solids) to being loosely packed (as liquids). Density refers to mass per volume but can also be described as the level of compactness of a substance. Thus, since liquid is not as compact as solid, it can be said to be less dense than solids.
Li(s) (answer A)
Li is strongest reducing agent because of the lowest standard reduction potential. when something is oxidized, it reduces another substance, becoming a reducing.Hence Lithium is strongest reducing agent. Reducing agent is stronger when it has a more positive oxidation potential.
Answer:
11.66 L.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If P and T are constant, and have different values of n and V:
<em>(V₁n₂) = (V₂n₁).</em>
V₁ = 25.5 L, n₁ = 3.5 mol.
V₂ = ??? L, n₂ = 3.5 mol - 1.9 mol = 1.6 mol.
<em>∴ V₂ = (V₁n₂)/(n₁)</em> = (25.5 L)(1.6 mol)/(3.5 mol) =<em> 11.66 L.</em>
Answer: when reactants and products are gases at STP.
Justification:
1) STP stands for standard temperature (0°) and pressure (1 atm).
2) According to the kinetic molecular theory of the gases, and as per Avogadro's principle, equal volumes of gases, at the same temperature and pressure, have the same number of molecules.
3) Since the coefficients in a balanced chemical equation represent number of moles, when reactants and products are gases at the same temperature and pressure, the mole ratios are the same that the volume ratios, and then the coefficients of the chemical equation represent the volume ratios.
