Answer:
(A) 28
Explanation:
To solve this problem we use the <em>PV=nRT equation</em>, where:
- P = 800 mmHg ⇒ 800/760 = 1.05 atm
- R = 0.082 atm·L·mol⁻¹·K⁻¹
- T = 25.0 °C ⇒ 25.0 + 273.16 = 298.16 K
We<u> input the data</u>:
- 1.05 atm * 2.00 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 298.16 K
And <u>solve for n</u>:
Now we calculate the gas' mass:
- Gas Mass = (Mass of Container w/ Gas) - (Mass of Empty Container)
- Gas Mass = 1052.4 g - 1050.0 g = 2.4 g
Finally we <u>calculate the unknown gas' molar mas</u>s, using<em> its mass and its number of moles</em>:
- Molar Mass = mass / moles
- Molar Mass = 2.4 g / 0.086 mol = 27.9 g/mol
So the answer is option (A).
<em>it is given as as under: :
</em>
The answer is (2) Copper. Because copper is consist of atom. If it is decomposed, the atom will be changed. While chemical change is just the break down and form of chemical bonds between atoms.
Answer:
Explanation:
When calculating an empirical formula from percentages, assume you have a 100g sample. This allows you to convert the percentages directly to grams, because X % of 100g is X grams.
So:
24.42 % = 24.42 g Ca, 17.07% = 17.07g N, 58.5% = 58.5g O
The next step is to divide each mass by their molar mass to convert your grams to moles.
24.42/40.08 = 0.6092 mol
17.07/14.01 = 1.218 mol
58.85/15.99 = 3.680 mol
Then you will divide all of your mol values by the SMALLEST number of moles. This gives you whole numbers that are the mole ratio (subcripts) of the empircal formula.
0.6092 mol/0.6092 mol = 1
1.218 mol/0.6092 mol = 2
3.680 mol/0.6092 mol = 6
So the empirical formula is
Answer:
Accuracy of a measured value refers to how close a measurement is to the correct value. The uncertainty in a measurement is an estimate of the amount by which the measurement result may differ from this value. Precision of measured values refers to how close the agreement is between repeated measurements.
Explanation:
