You'll need the specific heat capacity of aluminium to solve this question.
H=(0.005)(37-22)(specific heat capacity of aluminium)
Answer : The measurements are both precise and accurate.
Explanation :
Accuracy : It is defined as the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 50 kg and one person weighed 48 kg and another person weighed 55 kg. Then, the weight measured by first person is more accurate.
Precision : It is defined as the closeness of two or more measurements to each other.
For Example: If you weigh a given substance five times and you get 1.8 kg each time. Then the measurement is said to be precise.
Level of precision is determined by the maximum number of decimal places.
When the level of precision is very very less, the measurement can be considered as most precise and most accurate.
As we are given the standard value of the sample is 20.000 and the values measured by the balance are, 19.995, 20.005, 20.001.
Since these three values are in the range of +/- 0.005 from one another. So, we can say that the measurements are both precise and accurate.
Hence, the measurements are both precise and accurate.
Answer: 17.9 g
Explanation:
1) Chemical equation:
H₂ (g) + Cl₂ (g) → 2HCl (g)
2) mole ratios:
1 mol H₂ : 1 mol Cl₂ : 2 mol HCl
3) Since, the pressure and temperature conditions do not change, the same proportion is valid for the volumes. Then:
1 liter H₂ / 2 liter HCl = 5.15 liter H₂ / x
⇒ x = 5.5 × 2 / 1 = 11 liter HCl
4) Calculate the number of moles of HCl in 11 liter of HCl at STP
At STP, 1 mol of gas = 22.4 liter
⇒ 11 liter × 1mol / 22.4 liter = 0.491 mol HCl
5) Use the molar mass to convert 0.491 mol to grams
molar mass of HCl = 1.008 g/mol + 35.453 g/mol = 36.461 g/mol
mass in grams = nuumber of moles × molar mass = 36.461 g/mol × 0.491 mol = 17.90 g.
Answer:
Explanation:
Hello!
In this case, in a dilution process, water is added to a solute in order to decrease its concentration but increase the volume of the solution. It means that if we have 20.0 mL of a 12.0-M solution of HCl and we want a 0.500-M solution, we need to apply the following formula considering that the moles remain unchanged:
Thus, solving for the final volume is:
So plugging in the values we obtain:
Now, since the initial volume of acid was 20.0 mL and the final volume is 480 mL, the added volume of distilled water is:
Best regards!
