Cast Science Chemistry

1.  What element has 3 energy levels and 5 valence electrons?

• Arsenic 
• Phosphorus
• Yttruim
• Indium

Tags

NGSS.HS-PS1-1

1.  The atomic number of an element indicates which of the following?

• Neutrons in atom
• protons in atom
• neutrons and protons in atom
• sum of protons and electrons in atom

When a lithium atom forms an Li+ ion, the lithium atom

• gains proton
• loses proton
• gains electron
• loses electron

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NGSS.HS-PS1-2

1.  What characteristic is different between isotopes of an element?

• where listed on periodic table
• the net charge
• the mass of the protons 
• the # of neutrons in the nucleas

1.  An element has 10 electrons, 13 protons, and 15 neutrons.  What is the mass number?

• 23
• 28
• 15
• 25

1.  Which of the statements given concerning chemical bonding is FALSE? 

• ionic transfers electrons
• covalent occurs between nonmetals
• ionic occurs between cations and anions
• All chemical reactions require a transfer of electrons

Tags

NGSS.HS-PS1-2

NGSS.HS-PS1-3

1.  Which combination is most likely to form an ionic bond? 

• potassium-clorine
• oxygen-oxygen
• hydrogen-carbon
• xenon-bromine

Tags

NGSS.HS-PS1-2

1.  What is the correct formula for magnesium oxide?

• MgO₂
• MgO
• Mg₂O₂
• M₂O

Tags

NGSS.HS-PS1-2

1.  8.0 grams of magnesium react with unknown amount of nitrogen to form 12.0 grams of magnesium nitride as seen in the following equation. How many grams of nitrogen react with the magnesium?
3Mg + N2  Mg₃N₂   

• 8.0g
• 12.og
• 4.0g
• 20.0g

Tags

NGSS.HS-PS1-7

If an element is in period 2 and group 16 has how many valence electrons?

• 2
• 16
• 6
• 8

Tags

NGSS.HS-PS1-1