Answer:
0.877 mol
Step-by-step explanation:
We can use the<em> Ideal Gas Law </em>to solve this problem.
pV = nRT Divide both sides by RT
n = (pV)/(RT)
Data:
p = 646 torr
V = 25.0 L
R = 0.082 06 L·atm·K⁻¹mol⁻¹
T = 22.0 °C
Calculations:
(a) <em>Convert the pressure to atmospheres
</em>
p = 646 torr × (1 atm/760 torr) = 0.8500 atm
(b) <em>Convert the temperature to kelvins
</em>
T = (22.0 + 273.15) K = 295.15 K
(c) <em>Calculate the number of moles
</em>
n = (0.8500 × 25.0)/(0.082 06 × 295.15)
= 0.877 mol
The most common type of fluoride found in toothpaste is part of the compound sodium fluoride which has the chemical formula NaF
Answer:
the empirical (lowest raios) is
C2H4Cl
Explanation:
A compound is known to consist solely of carbon, hydrogen, and chlorine. Through elemental analysis, it was determined that the compound is composed of 24.27% carbon.
What is the empirical formula of this compound?
the compound has ONLY C, H, and Cl
the % Cl = 100% - 24.27% -4.03% = 71.7%
in 100 gm, there are 71.7 gm Cl, 24.27 gm C, and 4.03 gm H
the number of moles are Cl=71.7/70.91 =1.01= ~ 1
C = 24.27/12.0 = 2.02 =~ 2
H = 403/1.01 = 3.97 =~ 4
so the empirical (lowest raios) is
C2H4Cl
PH + pOH = 14
pH = 14 - pOH
pH = 14 - 8.7
pH = 5,3
This solution is <u>acidic</u>.
If pH<7 - acidic
If pH=7 - neutral
If pH>7 - basic