Chemistry Chapter 4

Knowing the numbers of protons in the atom of a neutral element enables you to determine which of the following?

The name of the element

What is true about the state of an individual atom?

The state of the atom depends on which element it is.

The formula of water, H2O, suggests:

There are two hydrogen atoms and one oxygen atom per water molecule.

Dalton assumed that all atoms of the same element are identical in all their properties. Explain why this assumption is not valid.

isotopes= atoms of the same element with different number of neutrons, therefore different masses.

How is an ion formed?

when an atom gains or loses an electron

One of the best indications of a useful theory is that it raises more questions for further experimentation than it originally answered. How does this apply to Dalton's atomic theory? Give examples.

1. atoms of elements not identical, isotopes 2. and atoms are divisible

The average mass of a carbon atom is 12.011. Assuming you were able to pick up only one carbon unit, the chances that you would randomly get one with a mass of 12.011 is

About 12%

The vitamin niacin (nicotinic acid, C6H5NOn) can be isolated from a variety of natural sources, such as liver, yeast, milk, and whole grain. It also can be synthesized from commercially available materials. Which source of nicotinic acid, from a nutritional view, is best for use in a multivitamin tablet? Why?

Doesn't matter because it produces the same product.

How does Dalton's Theory explain the Law of Constant Composition?

The atomic theory led to the creation of the law of multiple proportions.