Answer:
The correct answer is -
FALSIFIABLE:
Aloe vera gel can heal wounds by boosting cell renewal.
Drinking aloe juice can reduce the risk of lung cancer.
NON-FALSIFIABLE:
Aloe vera gel is the best natural skin moisturizer.
Aloe vera juice tastes better than carrot juice.
Explanation:
Falsifiable is the ability or chances of any hypothesis, claim or statement to be proved wrong. In such a hypothesis, it is possible to carry an experimental observation that disproves the idea in claim or question.
In the given examples
Aloe vera gel can heal wounds by boosting cell renewal.
Drinking aloe juice can reduce the risk of lung cancer.
There is no observation in the favor of the claim so there more likely to be falsifiable whereas, Aloe vera gel is the best natural skin moisturizer.
Aloe vera juice tastes better than carrot juice are more non-falsifiable as these are based on personal choice or experimental observation.
Answer:
A pure solid is heated and turns into a pure liquid.
Explanation:
No colour change recorded, only change of state, hence this is a physical change - physical changes I.e. change of state and temperature are not chemical reactions.
The molarity of a solution is the number of moles of a substance divided by the volume in liters prepared.
, where n is number of moles and V is the volume in liters.
In order to calculate the mass of solute we need to convert the volume and molarity to moles

Now that we have moles we use the relative formula mass of NaCO₃, We have 1 Na atom, 1 C atom and 3 O atoms, thus


Answer:
5 moles of electrons
Explanation:
The balance equation is as follow,
<span> 5 Ag</span>⁺ + Mn⁺²<span> + 4 H</span>₂O →<span> 5 Ag + MnO</span>₄⁻<span> + 8 H</span>⁺
Reduction of Ag:
Ag⁺ + 1 e⁻ → Ag
Or,
5 Ag⁺ + 5 e⁻ → 5 Ag
Oxidation of Mn:
Mn⁺² → MnO₄⁻ + 5 e⁻
Result:
Hence 5 moles of Ag⁺ accepts 5 electrons from 1 mole of Mn⁺².
Answer:
CO32−
Explanation:
We have to consider the valencies of the polyatomic ions involved. Recall that it is only a polyatomic ion with a valency of -2 that can form a compound which requires two sodium ions.
When we look closely at the options, we will realize that among all the options, only CO32− has a valency of -2, hence it must be the required answer. In order to be double sure, we put down the ionic reaction equation as follows;
2Na^+(aq) + CO3^2-(aq) ---------> Na2CO3(aq)