Atoms of elements that are in the same group have the same number of

The temperature of a sample of iron with a mass of 20.0 grams changed from 60.0ºC to 35.0ºC. How many Joules of heat were released?

Draw what a chromosome looks like during metaphase. identify the chromatids and the centromere

Nuclear forces are said to hold protons and neutrons together. what is it about the composition of the nucleus that requires the concept of nuclear forces?

The most important commercial process for generating hydrogen gas is the water-gas shift reaction:. CH4 (g) + H2O (g) → CO (g) + 3H2 (g). Use tabulated thermodynamic data to find ΔG° for this reaction at the standard temperature of 25°C.

The element nitrogen has an atomic weight of 14.0 and consists of two stable isotopes nitrogen-14 and nitrogen-15. The isotope nitrogen-14 has a mass of 14.0 amu and a percent natural abundance of 99.6 %.

You compare two layers to a because the crust and upper mantle are solid

A substance that speeds up the rate of a chemical reaction is called a. a catalyst. b. a lipid. c. a molecule. d. an element.

How many moles of Mgs203 are in 245g of the compound

A student was trying to obtain lithium by electrolysis of aqueous lithium chloride. Was he successful?

A Gouy balance is used to determine the magnetic susceptibility of a substance. A strong electromagnet is placed next to the sample, which is on a balance.