Chemicals Review

What does precise mean?

• Close to the accepted value
• All numbers close to the accepted value and together
• All numbers close together

What is 5.260 x 10 ⁵ expressed in standard notation?

• 0.00005260
• 5260
• 526000000
• 526000

What is the instrument to called and used for?

• a.  Filter for getting materials separated
• Filter for filtration or delivery of materials
• Funnel for getting materials separated
• Funnel for filtration or delivery of materials

Convert 436 K to degrees Celsius.

• 709
• 163
• 673
• 199

The nucleus of an atom is

• negatively charged and has a high mass.
• negatively charged and has a low mass
• positively charged and has a high mass.
• positively charged and has a low mass

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-8

The identity of an element can be determined on the basis of which of the following?

• the number of neutrons
• the number of protons
• the mass number 
• the number of electrons

A neutral atom of hydrogen-2 contains (same as ²H)

• 2 protons, 2 electrons, and 4 neutrons
• 2 protons, 2 electrons, and 2 neutrons.
• 1 proton, 1 electron, and 2 neutrons.
• 1 proton, 1 electron, and 1 neutron.

Tags

NGSS.MS-PS1-1

Which symbol correctly represents an element (D) whose atoms contain 15 protons   and 20 neutrons?

• ^35₁₅D
• ²⁰₁₅D
• ¹⁵₁₅D
• ¹⁵₂₀D

Tags

NGSS.MS-PS1-1

What is the name of an element that has a charge?

• Isotope
• Atom
• Ion

How many valence electrons does an atom of chlorine have?

• 17
• 7
• 3
• 2

Tags

NGSS.HS-PS1-1