Answer: 1.93 x 10^24 molecules
Explanation:
CH4 is the chemical formula for methane, the first member of the alkane family.
Based on Avogadro's law:
1 mole of any substance has 6.02 x 10^23 molecule
So, 1 mole of CH4 = 6.02 x 10^23 molecules
3.2 moles of CH4 = Z
To get the value of Z, cross multiply:
(Z x 1 mole) = (6.02 x 10^23 molecule x 3.2 moles)
Z•mole = 19.26 x 10^23 molecules•mole
Divide both sides by 1 mole
Z•mole / 1 mole = 19.26 x 10^23 molecules•mole/ 1mole
Z = 19.26 x 10^23 molecules
Place Z in standard form
Z = 1.93 x 10^24 molecules
Thus, 3.2 moles of ch4 has 1.93 x 10^24 molecules
Answer:
2.39 atm
Explanation:
We'll begin by calculating the number of mole in 0.41 g of neon (Ne). This can be obtained as follow:
Mass of Ne = 0.41 g
Molar mass of Ne = 20 g/mol
Mole of Ne =.?
Mole = mass / molar mass
Mole of Ne = 0.41 / 20
Mole of Ne = 0.0205 mole
Next we shall convert 200 mL to L.
1000 mL = 1 L
Therefore,
200 mL = 200 mL × 1 L / 1000 mL
200 mL = 0.2 L
Next, we shall convert 11 °C to Kelvin temperature.
T(K) = T(°C) + 273
T(°C) = 11 °C
T(K) = 11 + 273
T (K) = 284 K
Finally, we shall determine the pressure. This can be obtained as follow:
Mole of Ne (n) = 0.0205 mole
Volume (V) = 0.2 L
Temperature (T) = 284 K
Gas constant (R) = 0.0821 atm.L/Kmol
Pressure (P) =?
PV = nRT
P × 0.2 = 0.0205 × 0.0821 × 284
P × 0.2 = 0.4779862
Divide both side by 0.2
P = 0.4779862 / 0.2
P = 2.49 atm
Therefore, the pressure of the gas is 2.39 atm
The answer is C. If the Fours were all the way on the left it would make all of the zeros Significant figures.
B. Rovers are what you are looking for
Answer:
[OH-] = 6.17 *10^-10
Explanation:
Step 1: Data given
pOH = 9.21
Step 2: Calculate [OH-]
pOH = -log [OH-] = 9.21
[OH-] = 10^-9.21
[OH-] = 6.17 *10^-10
Step 3: Check if it's correct
pOH + pH = 14
[H+]*[OH-] = 10^-14
pH = 14 - 9.21 = 4.79
[H+] = 10^-4.79
[H+] = 1.62 *10^-5
6.17 * 10^-10 * 1.62 * 10^-5 = 1* 10^-14
