SC 4 P 10 2

The mass of an element is the sum of the atomic number and the number of __________.

• electrons

• ions

• neutrons

• protons

Tags

NGSS.MS-PS1-1

Which of the samples shown represents a pure substance?

• substances 1 and 2

• substances 2 and 3

• substances 3 and 4

• substances 1 and 4

Tags

NGSS.MS-PS1-1

The periodic table of the elements organizes elements according to their properties. A section of the periodic table is shown.

Which set of elements below is the most similar in chemical behavior?

• H, Be, Sc

• Fr, Ra, Rf

• Ti, V, Cr

• Be, Ca, Ra

Two common liquids, water and peroxide, are both formed with atoms of hydrogen and oxygen. If both substances discussed above are made of hydrogen and oxygen, how is the make-up of the two substances different?

• The number of atoms of each element is different.

• The number of protons in the atoms of each element is different.

• The number of protons in the atoms of each element is different.

• The number of protons in the atoms of each element is different.

Tags

NGSS.MS-PS1-1

What do carbon, hydrogen, and oxygen atoms have in common?

• the same number of protons

• he same number of electrons

• neutrons located outside of the nucleus

• electrons located outside of the nucleus

Sodium metal (Na) reacts violently when mixed with water and produces sodium hydroxide (NaOH) and hydrogen gas (H2).

Which metal would most likely react in a similar fashion?

• magnesium (Mg)

• aluminum (Al)

• potassium (K)

• titanium (Ti)

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

Which of these is not an example of a pure substance?

• aluminum can

• milk

• table salt

• water

An atom's atomic number of an element is the number of protons in the nucleus of one of its atoms.

• True

• False

Tags

NGSS.MS-PS1-1

The nucleus of an atom is its tiny central region, and comprises the bulk of the atom's mass, containing the protons and neutrons.

• True

• False

Shelby filled three empty soda bottles with 5 g of steel wool, a material used for cleaning that also rusts quickly. She added 100 mL of water to each bottle and then resealed the bottle. She placed each bottle in one of three different locations: in a refrigerator at 3 °C, in a room at 25 °C, and in a warm kitchen at 30 °C. She observed the bottles every day for a week and recorded the amount of rust that formed on the steel wool. Which research question does this experiment best investigate?

• Does a gas form when steel wool rusts?

• Does the temperature in a room vary widely over time?

• Does the amount of water effect how quickly steel wool rusts?

• Does temperature affect the amount of rust that forms on steel wool?