Using a more concentrated HCl solution and Crushing the CaCO₃ into a fine powder makes the reaction to occur at a faster rate.
<u>Explanation:</u>
CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(aq) + CO₂(g)
When calcium carbonate reacts with hydrochloric acid, it gives out carbon-dioxide in the form of bubbles and there is a formation of calcium chloride in aqueous medium.
The rate of the reaction can be increased by
- Using a more concentrated HCl solution
- Crushing the CaCO₃ into a fine powder
When concentrated acid is used instead of dilute acid then the reaction will occur at a faster rate.
When CaCO₃ is crushed into a fine powder then the surface area will increases thereby increasing the rate of the reaction.
Answer:
The answer is 465.6 mg of MgI₂ to be added.
Explanation:
We find the mole of ion I⁻ in the final solution
C = n/V -> n = C x V = 0.2577 (L) x 0.1 (mol/L) = 0.02577 mol
But in the initial solution, there was 0.087 M KI, which can be converted into mole same as above calculation, equal to 0.02242 mol.
So we need to add an addition amount of 0.02577 - 0.02242 = 0.00335 mol of I⁻. But each molecule of MgI₂ yields two ions of I⁻, so we need to divide 0.00335 by 2 to find the mole of MgI₂, which then is 0.001675 mol.
Hence, the weight of MgI₂ must be added is
Weight of MgI₂ = 0.001675 mol x 278 g/mol = 0.4656 g = 465.6 mg
Answer:
a) if the liquid is not vaporized completely, then the condensed vapor in the flask contains the air which is initially occupied before the liquid is heated. When calculating the molar mass of the vapor the moles of air which are initially present are not excluded, so that the molar mass of the vapor would be an increase in value.
b) While weighing the condensed vapor, the flask should be dried. If the weighing flask is not dried then the water which is layered on the surface of the flask is also added to the mass of the vapor. Therefore, the mass of the vapor that is calculated would be increase.
c) When condensing the vapor, the stopper should not be removed from the flask, because the vapor will escape from the flask and a small amount of vapor will condense in the flask. Therefore, the mass of the condensed vapor would be In small value.
d) If all the liquid is vaporized, when the flask is removed before the vapor had reached the temperature of boiling water, then the boiling
temperature of that liquid would be lower than that of the boiling temperature of the water.Therefore, the liquid may have more volatility.
Explanation:
The given compounds are oxyacids and in these compounds more is the electronegativity of the central atom more will be its acidic strength.
This is because more is the electronegativity of the central atom more will be the polarity of OH bond. As a result, the compound can readily lose 
ion.
Also, more is the electronegativity of central atom more will be the stability of conjugate base formed.
Thus, we can conclude that given compounds are arranged in increasing acid strength as follows.
HOI < 
< 
< HOF
