i am pretty sure it would be a chemical change so A
Answer:
The properties of the Hardness are:
Hardness is a physical property
Hardness is indicative of the strength of chemical bonds between elements.
Diamond can scratch quartz Explanation:
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
Answer:
0.0685 mL
Explanation:
To find the volume of the sample, divide the mass by the density.
(1.00 g)/(14.6 g/mL) = 0.0685 mL
M=mol/liter
We know that we have 150ml=.15 L and .1 mol of HCl
Rearranging the molarity equation, we get
mol=M*l
mol=(.15)(.1)
=.015 mol
