Answer:
D
Explanation:
When lead ions and sulfate ions bond, they form sediment so neither a nor b can be the answer.
The important thing is that two nitrate ions were originally bonded with one lead ion, while two potassium ions bonded with a sulfate ion.
Finally, since potassium and nitrate ions don't form sediment these two ions must remain. Therefore the answer is D
To convert the given value to the desired one, use the proper unit conversions and dimensional analysis. Use the following conversion for the first set.
1 g = 100 cg
1 L = 1000 mL
Using the concept presented above,
V = (59800 cg/L)(1 g/100 cg)1 L/1000 mL)
V = 0.598 g/mL
Correct question
The density of liquid mercury is 13.6 g/mL. What is its density in units of lb/in3? (2.5 cm = 1 in., 2.205 lbs= 1 kg., 1000 g =1 kg, 1 mL = 1 cm³)
Answer:
Explanation:
Given that;-
The density = 13.6 g/mL
Also, 1 kg = 2.205 lb
1 kg = 1000 g
So, 1000 g = 2.205 lb
1 g = 0.002205 lb
Also,
1 in = 2.54 cm
1 in³ = 16.39 cm³
1 cm³ = 1 mL
So, 1 in³ = 16.39 mL
1 mL = 0.061 in³
The expression for the calculation of density is shown below as:-
Thus,
Answer:
- <em>The average mass of calcium in each sample is: </em><u>0.978 g</u>
<em />
- <em>The absolute uncertainty is: </em><u>0.008 g</u>
Explanation:
The <em>absolute uncertainty </em>of the total samples indicated in the statement is ± 0.1 g.
When you multiply or divide quantities with uncertainties, you calculate the final uncertanty by adding the <em>relative uncertainties</em> together.
The relative uncertainty is the absolute uncertainty divided by the quantity:
- Relative uncertainty = 0.1g / 12.2 g = 0.008
The average mass of calcium is calculated using proportions, along with the molar masses:
- Molar mass of calcium: 40.078 g/ mol (from a periodic table)
- Molar mass of calcite: 100.085 g/mol (given)
Proportion:
- 40.078 g of calcium / 100.085 g of calcite = x / 12.2 g of calcite
- x = 12.2 × 40.078 / 100.085 g = 4.89 g calcium
So the total mass of calcium in the five samples is 4.89 g, and the average mass in each sample is:
- Average mass = total mass of five samples / number of samples
- Average mass = 4.89 g / 5 = <u>0.978 g of calcium</u>
So, the first answer is that the average mass of calcium in each sample is 0.978 g ( keep 3 signficant figures, such as the quntitiy 12.2 shows, as you have only used multiplication and division).
The absolute uncertainty of each sample is the relative uncertainty multiplied by the average mass of calcium of the five samples, rounded to one decimal:
- Absolute uncertainty = 0.978 g × 0.008 ≈ 0.008 g
The answer to the secon question is that the absolute uncertaingy of calcium in each sample is 0.008 g.
