Explanation:
Since HF is a weak acid, the use of an ICE table is required to find the pH. The question gives us the concentration of the HF.
HF+H2O⇌H3O++F−HF+H2O⇌H3O++F−
Initial0.3 M-0 M0 MChange- X-+ X+XEquilibrium0.3 - X-X MX M
Writing the information from the ICE Table in Equation form yields
6.6×10−4=x20.3−x6.6×10−4=x20.3−x
Manipulating the equation to get everything on one side yields
0=x2+6.6×10−4x−1.98×10−40=x2+6.6×10−4x−1.98×10−4
Now this information is plugged into the quadratic formula to give
x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)−−−−−−−−−−−−−−−−−−−−−−−−−−−−√2x=−6.6×10−4±(6.6×10−4)2−4(1)(−1.98×10−4)2
The quadratic formula yields that x=0.013745 and x=-0.014405
However we can rule out x=-0.014405 because there cannot be negative concentrations. Therefore to get the pH we plug the concentration of H3O+ into the equation pH=-log(0.013745) and get pH=1.86
Hey there!
325 mL in liters:
325 / 1000 => 0.325 L
1 mole ( Ne ) ------------- 22.4 L ( at STP )
moles ( Ne ) ------------ 0.325 L
moles Ne = 0.325 * 1 / 22.4
moles Ne = 0.325 / 22.4
moles Ne = 0.0145 moles
hope this helps!
Answer:
0.29 moles of PbCl₂
Explanation:
Given data:
Mass of lithium chloride = 24.3 g
Moles of PbCl₂ = ?
Solution:
Chemical equation;
PbSO₄ + 2LiCl → PbCl₂ + Li₂SO₄
Number of moles of LiCl:
Number of moles = mass/ molar mass
Number of moles = 24.3 g/ 42.394 g/mol
Number of moles = 0.57 mol
Now we will compare the moles of PbCl₂ with LiCl .
LiCl : PbCl₂
2 : 1
0.57 : 1/2×0.57 = 0.29 mol
Answer:
2H₂ + O₂ → 2H₂O
Explanation:
The expression of the equation is given as:
_H₂ + 2O₂ → 2H₂O
Now for expression above,
Reactants Products
H 2 4
O 4 2
to balance the equation, we use 2 moles of hydrogen gas and 1 mole of oxygen gas;
2H₂ + O₂ → 2H₂O