Answer:
The mass of air is 8.245 g
The mass of helium is 1.145 g
The difference is 7.1 g
Explanation:
Total mass (air and helium) = PVM/RT
P is total pressure in the tire = 120 Psi = 120/14.696 = 8.17 atm
V is volume of the tire = 860 mL = 860 cm^3
M is the total molar mass of air and helium = 28.8 + 4= 32.8 g/mol
R is gas constant = 82.057 cm^3.atm/mol.K
T is temperature = 26°C = 26+273 = 299 K
Total mass = 8.17×860×32.8/82.057×299 = 9.39 g
Mass of air = mass fraction of air × total mass = 28.8/32.8 × 9.39 = 8.245 g
Mass of helium = total mass - mass of air = 9.39 - 8.245 = 1.145 g
Difference = 8.245 - 1.145 = 7.1 g
There are 2 Ca, 4 H (2*2) and 4 O (2+2) on the left hand side. So there should be the same number of atoms 2Ca and 4(O+H) on the right hand side. The reaction is a synthesis (making something new), rather than a decomposition (destroying something).
The answer is Two molecules of Ca(OH)2 should be produced during the synthesis reaction.
Answer:
0.07172 L = 7.172 mL.
Explanation:
- We can use the general law of ideal gas: <em>PV = nRT.
</em>
where, P is the pressure of the gas in atm (P = 1.0 atm, Standard P).
V is the volume of the gas in L (V = ??? L).
n is the no. of moles of the gas in mol (n = 3.2 x 10⁻³ mol).
R is the general gas constant (R = 0.0821 L.atm/mol.K),
T is the temperature of the gas in K (T = 273 K, Standard T).
<em>∴ V = nRT/P =</em> (3.2 x 10⁻³ mol)(0.0821 L.atm/mol.K)(273 K)/(1.0 atm) = <em>0.07172 L = 7.172 mL.</em>
Answer:
a) a space in an atom where an electron is most likely to be found
Explanation:
Atomic orbital is the mathematical function which describes wave-like behavior of the electrons present in the atom.
It is used to calculate probability of finding the electron of the atom in any region around nucleus of the atom. Atomic orbital is the physical region or a three dimensional space where the probability of finding the electron is more than 90% which also means that the space where an electron is most likely to be found. They are boundless space and have definite energy.
Option A best describes atomic orbital.
Answer:
1.48 moles of SeCl6 are needed
Explanation:
Based on the reaction:
SeCl6 + O2 → SeO2 + 3Cl2
<em>1 mole of SeCl6 reacts producing 3 moles of Cl2.</em>
To solve this question we need to use the conversion factor:
1mol SeCl6 = 3mol Cl2
As we want to produce 4.45 moles of Cl2, we need:
4.45 mol Cl2 * (1mol SeCl6 / 3mol Cl2) =
<h3>1.48 moles of SeCl6 are needed</h3>