A sample of urea contains 1.121 g of N, 0.161 g of H, 0.48 g of C, and 0.64 g of O. What is the empirical formula of urea?

What scientific instrument was used to dicover that not all atoms of neon have the same mass?

All fungi are. prokaryotes? eukaryotic? unicellular? multicellular

A 1.0L buffer solution contains 0.100 mol of HC2H3O2 and 0.100 mol of NaC2H3O2. The value of Ka for HC2H3O2 is 1.8Ă-10â'5. Part A Part complete Calculate the pH of the solution upon the addition of 0.015 mol of NaOH to the original buffer.

To identify a diatomic gas (X2), a researcher carried out the following experiment: She weighed an empty 2.2-L bulb, then filled it with the gas at 2.00 atm and 27.0 ∘C and weighed it again. The difference in mass was 5.1 g. Identify the gas.

The formation of gas resulting from the escape

A 27.40 g sample of liquid mercury is initially at 158.30°C. If the sample is heated at constant pressure ( = 1 atm), kJ of energy are needed to raise the temperature of the sample to 376.20°C. How much energy in kJ is required?

When a sample of gas is cooled, it condenses into a liquid. In which of the following ways do the molecules of the original gas sample compare with the molecules of the liquid? a. The molecules weigh less as a gas than they do as a liquid. b.

In a group 1 analysis, a student obtained a precipitate containing both AgCl and PbCh. Which of the following reagents would enable separation of AgCl (s) from PbCl (s) ? O Hys 0 Na2CO3 o KOH O NH3 O

Round to four significant figures 0.00238866

Gases are unique because it is the only phase that can be compressed can flow is composed of moving particles cannot be compressed