Search & Filtering
Calculate the value of the ionization constant Ka, if the pKa is 5.64
What is the pKa of benzoic acid if Ka for benzoic acid 6.3 x 10.5?
A solution has a pOH of 13.23. What is the pH of this solution?
What is the hydroxide ion concentration in a solution that has a pOH of 7.50?
What is the pOH of a solution that has a hydroxide ion concentration of 2.82 x 10-8 M?
Magnesium hydroxide solid is added into 50 cm^3 of 1.5 mol dm^-3 nitric acid. The mixture is stirred until there is no more change observed. Calculate the mass of magnesium hydroxide needed to react completely with the nitric acid
mass (g) of 4.04x10^20 molecules of dinitrogen pentoxide
The homogeneity of the chloride level in a water sample from a lake was tested by
analyzing portions drawn from the top and from near the bottom of the lake, with the
following results in ppm Cl:
Top Bottom
26.30 26.22
26.43 26.32
26.28 26.20
26.19 26.11
26.49 26.42
(a) Apply the t test at the 95% confidence level to determine if the chloride level from
the top of the lake is different from that at the bottom.
(b) Now use the paired t test and determine whether there is a significant difference
between the top and bottom values at the 95% confidence level.
(c) Why is a different conclusion drawn from using the paired t test than from just
pooling the data and using the normal t test for differences in means?
A quantity of a certain perfect gas is compressed from an initial state of 0.085 m3 ,1 bar to a final state of 0.034 m3 , 3.9 bar. The specific heat at constant volume is 0.717 kJ/ kg K, and the specific heat at constant pressure is 1.025 kJ/kg K. The observed temperature rise is 146 K. Calculate the specific gas constant R to three decimal places and state the unit.
