A container hold 3 gases: oxygen, carbon, dioxide, and helium. The partial pressure for two of the gases are oxygen: 3.00 atm and carbon dioxide: 4.00 atm. If the total pressure in the container is 20 atm what is the partial pressure of helium.​

If a solution is considered basic, then a) the hydroxide ion and hydronium ion concentrations are equal. b) the hydroxide ion concentration is less than the hydronium ion concentration. c) the hydronium ion concentration is greater than the hydroxide ion concentration. d) the hydroxide ion concentration is greater than the hydronium ion concentration.

The yearly amounts of carbon emissions from cars in belgium are normally distributed with a mean of 13.9 gigagrams per year and a standard deviation of 5.8 gigagrams per year. find the probability that the amount of carbon emissions from cars in belgium for a randomly selected year are between 11.5 gigagrams and 14.0 gigagrams per year. a. 0.340 b. 0.660 c. 0.167 d. 0.397

What does the symbol (–hfus) indicate in a phase change?