Select the correct answer.

An element has atomic number 10 and an atomic mass of 20. How many neutrons are in the atom of this element?

A. 10

b. 20

D. 0

E. 200

If 45.0 mL of 0.25 M HCl is required to completely neutralize 25.0 mL of NH3, what is the concentration of the NH3 solution? Show all of the work needed to solve this problem. HCl + NH3 yields NH4Cl

Which of these best describes a scientific law ... ? 1. A rule made by a government 2. A rule that does not depend on observable evidence 3. A statement which varies under the same conditions 4. A statement about how things act in the natraul world

The mass of 0.125 mol of nitrogen is A 224g B 1.75g C 3.50g D 112g

Name any two polymers which are formed by the process of condensation polymerization.

Which results when an atom has such a strong attraction for electrons that it pulls one or more electrons completely away from another atom?

What is the element Ar classified as in the periodic table?

Using the clausius clapeyron equation determines the heat of vaporization from experimental measurements of vapor pressure. the vapor pressure of dichloromethane is measured as a function of temperature and the results are tabulated.

Why is it important for people to understand how to properly dispose of waste in a watershed?

As you travel from a solid to a gas, energy is being absorbed or given off?

Do step 3 as outlined in the lab guide. Record your results in the appropriate blanks. A = B = C = D = E = F = G = H = A 3-column table with 9 rows. Column 1 is labeled Time half-life cycles, n with entries Initial, 1, 2, 3, 4, 5, 6, 7, 8.