Core Ideas of Chemistry

How did Mendeleev arrange the elements?

• alphabetically

• by density

• by melting point

• by atomic mass

The horizontal row on the periodic table is called a

• group

• family

• period

• atomic number

What are the 3 particles that make-up the atom?

• protons, neutrons, and isotopes

• neutrons, isotopes, and electrons

• positives, negatives, and electrons

• protons, neutrons, and electrons

Tags

NGSS.MS-PS1-1

What's a valence electron?

• electrons in the second energy level

• electrons in the outermost energy level

• the atomic number

• electrons in the first level

Tags

NGSS.MS-PS1-1

Properties that describe how a substance reacts with other substances are called?

• Chemical properties

• Physical properties

Tags

NGSS.MS-PS1-2

NGSS.MS-PS1-5

The first ideas related atoms was that matter ​ (a)   be ​divided into smaller pieces forever.

• cannot

• can

Who developed the atomic theory? (a)  

• Dalton

• Thomson

• Chadwick

• Rutherford

Democritus believed that the smallest particles, were atomos, the Greek word for 

• small

• uncut or indivisible

• basic

What was Dalon's atomic theory about ?

• Matter is made tiny particles called atoms.

• Atoms combine in whole numbers.

• Atoms of an element are identical in mass and properties.

• Different elements have different properties.

• They are divisible into protons. It contains electronic shells.

Tags

NGSS.HS-PS1-7

These are found on the Periodic Table.

• Compounds

• Elements

• Mixtures