17) 8.4 / 20 x 100
18) 20 . 0.5150
19) 6,50% because (as you said) the law of definite proportions states that regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
Answer:
2Na⁺ (aq) and 2OH⁻(aq)
Explanation:
Spectator ions:
Spectator ions are those ions which are same on both side of chemical reaction. These ions are same in the reactant side and product side. Their presence can not effect the chemical equilibrium that's why when we write the net ionic equation these ions are neglect or omitted.
Given ionic equation:
Ba⁺²(aq) + 2OH⁻(aq) + 2Na⁺ (aq) + CO²⁻₃(aq) → BaCO₃(s) + + 2Na⁺ (aq) + 2OH⁻(aq)
In given ionic equation by omitting the spectator ions i.e, 2Na⁺ (aq) and 2OH⁻(aq) net ionic equation can be written as,
Net ionic equation:
Ba⁺²(aq) + CO²⁻₃(aq) → BaCO₃(s)
Answer:
Explanation:
Salt water intrusion can cause the <u><em>fresh</em></u> water in wells to become contaminated with<u><em> salt</em></u>water.
Answer with Explanation:
The units used to express the densities of gases are different from those of solids and liquids because the particles in gas are widely separated from each other, unlike the particles in solid and liquid <u><em>which are almost the same</em></u>. The particles in solid are very close together. Considering it melts (if it's an ice), it will turn into a liquid and the change in volume is slightly greater only. However, if the liquid evaporates and transitions into a gas, <u>the volume becomes largely different from its solid and liquid state</u>. This is because the particles are much farther apart and free to move.
