31. The mass number of a nucleus is:

a) always less than its atomic number: b) the sum of the number of protons and neutrons present in

the nucleus; c) always more than the atomic weight; d) a fraction.

How many liters of NH3, at STP, will react with 16.2 g O2 to form NO2 and water

How long would it take for 1.50 mol of water at 100.0 âc to be converted completely into steam if heat were added at a constant rate of 20.0 j/s? express your answer to three significant figures and include the appropriate units?

If your chemical formula is 3H2O what is the 2 called

What is the effect of temperature on molarity?

Combustion analysis of a hydrocarbon produced 33.01 g co2 and 27.02 g h2o. calculate the empirical formula of the hydrocarbon.

One year ago, you sold a put option on 100,000 euros with an expiration date of 1 year. you received a premium on the put option of $0.04 per unit. the exercise price was $1.22. assume that 1 year ago the spot rate of the euro was $1.

Calculate the product of 0.0002115m and 0.0000405m. Express the answer in scientific notation

How do the different spheres of Earth interact? Volcanic eruptions are natural phenomena in the. They sometimes erupt, spilling out lava and dust. The lava solidifies, forming new landmasses.

Differentiate between mass, volume, and density. Explain why only changing the shape of an object would have no effect on its density.

Describe the properties of noble gases. Based on their electronic arrangement, explain whether they can exist alone in nature.