Answer:
29 mL
Explanation:
<h3>Equation</h3>
The question needs us to find the volume of the liquid. The equation for volume using density and mass is:
Volume = Mass / Density
<h3>Solve</h3>
We can substitute the given values for density and mass into the equation:
<h3>Additional Comments</h3>
The answer we obtained (29 mL) is rounded to two significant figures. When multiplying or dividing, the amount of significant figures in the final answer is always the least amount of significant figures in one of the values.
Below are the significant figure rules:
Nonzero digits will always be significant (eg. 54 --> 2 significant figures)
Zeroes at the beginning of a number will never be significant (eg. 0.1 --> 1 significant figure)
Zeroes between two nonzero digits will always be significant (eg. 504 --> 3 significant figures)
Zeroes following a number will always be significant if the number contains a decimal point (eg. 40.0 --> 3 significant figures)
Answer:
1. (NH₄)₂S(s) -----> NH₄+(aq) + S²-(aq)
2. Al³+ (aq) + PO₄³+ (aq) ----> AlPO₄ (s)
Explanation:
The dissociation of ammonium sulphide, (NH₄)₂S when dissolved in water is given in the equation below:
(NH₄)₂S(s) -----> NH₄+(aq) + S²-(aq)
However very little S²- ions are present in solution due to the very basic nature of the S²- ion (Kb = 1 x 105).
The ammonium ion being a better proton donor than water, donates a proton to sulphide ion to form hydrosulphide ion which exists in equilibrium with aqueous ammonia.
S²- (aq) + NH₄+ (aq) ⇌ SH- (aq) + NH₃ (aq)
Aqueous solutions of ammonium sulfide are smelly due to the release of hydrogen sulfide and ammonia, hence, their use in making stink bombs.
2. The reaction between aluminium nitrate and sodium phosphatein aqueous solution is a double decomposition reaction whish results in the precipitation of insoluble aluminium phosphate. The equation of the reaction is given below :
Al(NO₃)₃ (aq) + Na₃PO₄ (aq) ----> AlPO₄ (s) + 3 NaNO₃ (aq)
The net ionic equation is given below:
Al³+ (aq) + PO₄³+ (aq) ----> AlPO₄ (s)
<h3>
<u>Answer:</u></h3>
<u>1 mole of a gas at STP occupies 22.4 L volume </u>
<u>Now the volume is given =78.4 therefore,</u>
<u>No. of moles of gas = 78.4 ÷ 22.4 = 3.5 moles</u>
<u>I hope it helps you~</u>
The answer is dissolved salts
