Chp. 1- General Chemistry

Macroscopic Atoms; big atoms

About how many different types of atoms are there?

100

When different atoms combine, what do they form?

All known substances

Properties of a substance are determined by...

The arrangement of its atoms

What is composed of atoms?

Matter

What is the smallest part of an element?

Atom

What is a molecule?

2 or more atoms joined and acting as a unit.

What are diatomic molecules?

Chemical elements that naturally possess 2 atoms.

O2 and H2 are examples of...

Diatomic molecules

Help solve problems and study nature/the basis on which a scientific inquiry is conducted.

Scientific method

What are the steps of the scientific method?

1. Observation 2. Questions3. Hypothesis 4. Experiment5. Conclusion

What is a theory?

A set of tested hypotheses that gives an overall explanation of some natural phenomenon.

A statement on how a particular phenomenon occurs.

Law

An attempt to explain why a phenomenon occurs.

Theory

A given compound always contains exactly the same proportion of elements by mass.

Law. of definite proportion

The total mass of materials isn't affected by a chemical change in those materials.

Law of Conservation of Mass

What does the law of conservation of mass state?

mass is neither created nor destroyed

What is Dalton's Atomic theory composed of? (4)

1. Each element is made up of atoms2. Atoms of given element are identical, but the atoms of different elements are different.3. Chemical compounds are formed when atoms of different elements combine.4. Chemical reactions involve changes in the way atoms are bound together without actually changing the atoms.

At the same temperature and pressure, equal volumes of different gases contain the same number of particles.

Avogadro's hypothesis

Atoms are made of a positively charged cloud. and electrons are embedded at random.

Plum Pudding Model

What are the 3 types of radioactive emission?

Gamma Rays (Y), Beta particles (B), Alpha particles (a)

What are gamma rays?

high energy light

What are beta particles?

High-speed electrons

What are alpha particles?

Positively charges and made up of 2 protons and 2 neutrons

What 4 things compose an atom?

Protons, electrons, neutrons, nucleus

What are protons?

Positively charged *equal the magnitude to electrons neg charge

What are electrons?

Negatively charged particles

What are neutrons?

No charge *Usually have the same mass as proton

What is smaller than an atom, extremely dense, and accounts for almost all of the atom's mass?

Nucleus

What has the same number of protons, but not neutrons?

Isotopes

What are ions?

Charged atoms

What are the 2 types of ions?

anions, cations

What is the charge of an atom usually?

It's usually electrically neutral, but can be assigned a charge by either removing or adding an electron.

What is a cation?

A positive ion

What is a anion?

A negative ion

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