Answer:

Explanation:
1. Calculate the molar mass of N₂H₄
2N = 2 × 14 = 28
4H = 2 × 1 = <u> 4</u>
Tot. = 32
2. Calculate the mass percent of N

The formula to find yield is
(Actual Yield)/(Theorectical Yield) x100
Just do the math.
85.22% x 113 = 96.2986
Convert it to 3 significant figures
Ans: 96.3g
Answer:
- Brush off any chemical dust around the balance after each use
- Alert your TA or instructor about any issues with the balance
Explanation:
The best practices while sharing a lab balance with other students includes alerting your TA or instructor about issues with the balance and Brushing off any chemical dust around the balance after each use. the practices will help to avert/reduce the work hazards associated with working with a balance.
Brushing off any chemical dust after each use will reduce the chemical hazards in the lab while Alerting your instructor about any issues with the balance helps to eliminate mechanical hazards that a faulty balance can pose
Answer:
14.9075 g, 28.67%, 0.11%
Explanation:
The mean concentration of calcium = summation x / frequency
= ( 14.92 + 1491 + 14.88 + 14.92 ) /4 = 14.9075 g
Standard deviation = √(summation (x - μ)² /n) = √ ( ((14.92 - 14.9075)² +(14.91 - 14.9075)² + (14.88 - 14.9075)² + ( 14.92 - 14.9075)²) / 4) = 0.0164
b) percent error = abs(14.9075 - 20.90) / 20.90 × 100 = 28.67%
c) relative standard deviation = standard deviation / mean × 100 = 0.0164 / 14.9075 × 100 = 0.11%
d) The accuracy of the measure is the measurement compared to the actual which according to the standard set by the instructor (5%error) is not very accurate because the percent error is high (28.67%) while the relative standard deviation is quite low ( 0.11%) which means the measurement precision is very high.
The student will have to redo the experiment because the experiment was not too accurate since the percent error is way higher than the set value (5%) although the precision was high.