You measure the pH of rainwater at 5.4. Calculate the partial pressure of carbon dioxide (assume only CO₂ is present).

PLEASE BE VERY CLEAR WITH WHERE EVERYTHING COMES FROM

Which substances given below produce a basic solution when dissolved in water?

NaCl

KOH

Sucrose

NH3

Vinegar

Suppose an everyday chemical reacts with vinegar. Is the substance more likely to be an acid or a base? Justify your answer.

A 25.0 mL sample of 0.30 M HCOOH is titrated with 0.20 M KOH. What is the pH of the solution after 25.0 mL of KOH has been added to the acid? Ka = 1.8x10^-4

Determine the electron geometry, molecular geometry, and idealized bond angles for each of the following molecules. In which cases do you expect deviations from the idealized bond angle?

CF4

NF3

OF2

H2S

Given that the density of air at 0.987 bar and 27°C is 1.146 kg m⁻³, calculate the mole fraction and partial pressure of nitrogen and oxygen assuming the following conditions.

(a) air consists only of these two gases
mole fraction nitrogen
  
mole fraction oxygen
  
partial pressure nitrogen
  bar
partial pressure oxygen
  bar

(b) air also contains 1.0 mole percent Ar
mole fraction nitrogen
  
mole fraction oxygen
  
partial pressure nitrogen
  bar
partial pressure oxygen
  bar
partial pressure argon
  bar

1.) What is the pH of a solution created by combining 1.34 mole of HOBr and 0.47 mole NaOH in a 1.00L solution? K_{a HOBr} = 2.5 x 10<sup>-9

2.)</sup> What is the pH after 0.24 moles of NaOH is added to a buffer containing 1.00 moles of NH₃ and 1.00 moles NH₄Cl ? K_{b NH3} = 1.8 x 10<sup>-5

3.)</sup> What is the pH of a buffer made by combining 0.69 moles HOBr with 0.65 moles NaOBr in a 100.00mL solution? K_{a HOBr} = 2.5 x 10^-9

A 100 g piece of copper, initially at 95,0 C ,
is dropped into 200 g of water. If initial temperature of
water is 1 5 C, what is final temperature of the system, if the heat lost to surounding is ignored

please, step by step solution.

Physical Chemistry:

Calculate ΔG for the isothermal compression of 10.0 g of water from 1.0 atm to 100.0 atm at 25°C

What is the total enthalpy change when 100.0 g of solid NH3 at -150.0 degrees Celcius is changed to gas at 100 degrees Celcius?

I've done this problem several times and keep getting the answer of 223 kj, but in class we were told the correct answer is 237 kj. Please show all your steps/work so I can see what I'm doing wrong. Thank you!

Calculate the mass of methane that must be burned to provide enough heat to convert 266.0 g of water at 39.0°C into steam at 110.0°C. (Assume that the H₂O produced in the combustion reaction is steam rather than liquid water.)

The enthalpy of fusion of titanium is 20.9 kJ/mol. How many grams of titanium can be melted by adding 58.0 kJ of energy to the metal at its melting point?

Determine the oxidation states of carbon in the following substances.

CH₄                      _________

CH₂Cl₂        _________

SiC            _________   

CF₂Cl₂                 _________

C₂H₆                    _________                      

C(s)             _________

C₄H₁₀                 _________

C₆H₁₂O₆     _________

CH₃CHO    ________

CO              _________

C₂H₄                    _________

CO₂                      _________

C₂H₂                    _________

CO₃^{2 -}                _________

What is the pH at the equivalence point in the titration of a 21.2 mL sample of a 0.319 M aqueous nitrous acid solution with a 0.408 M aqueous potassium hydroxide solution?

What is the pH of a 0.055 M solution of sodium cyanide (NaCN)? The K_a value for hydrocyanic acid (HCN) is 6.2 x 10^-10.

Select one:

a. 10.97

b. 10.08

c. 8.77

d. 3.03

e. 5.23