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The electron configuration of an atom determines how the atom reacts with other atoms. Examine the periodic table and determine which of the following substances is least likely to react with another substance.
Which of the following elements can be characterized as a metal?
The number of neutrons in a chlorine atom is –
All atoms are electrically neutral. Atoms become electrically charged when they-
lose and gain electrons.
gain and lose protons.
have the same number of neutrons and protons.
have a different number of neutrons and protons.
Group I (Alkali Metals) includes Lithium (Li), Sodium (Na), and Potassium (K). These elements have similar chemical properties because they have the same __
numbers of protons and neutrons in the nucleus.
numbers of protons and electrons in the nucleus.
numbers of electrons in the outer energy level.
numbers of neutrons in the outer energy level.
Which of the following is the most important factor in determining an element’s place in the periodic table?
Number of protons
Number of neutrons
Which best represents how electrons are arranged in the energy levels of a carbon atom?
First level = 1 electron, Second = 5 electrons
First level = 2 electrons, Second = 4 electrons
First level = 3 electrons, Second = 3 electrons
First level = 4 electrons, Second = 3 electrons
Silicon’s atomic number is 14. This means that silicon has -
14 protons in its nucleus.
14 atoms in every molecule.
a boiling point of 14OC
an atomic radius of 14 micrometers
Which of the following chemical formulas represent the reactants in this chemical equation?
CH4 + 2O2 → CO2 + 2H2O
CH4 and H2O
O2 and CO2
CH4 and 2O2
CO2 and 2H2O
The subscripts in this formula C6H12O6 provide information about -
The number of compounds
The number of atoms per element
The number of molecules
The name of each element
Which number could replace the “?” to balance this equation?
3H2 + 2Cl3 → _?_ HCl
Which element can be identified as having 16 protons?
What is the correct charge of the nucleus?
All the following chemical equations are balanced except -
C3H8 + O2 --> 3CO2 + 4H2O
RbBr + AgCl --> AgBr + RbCl
WO3 + 3H2 --> W + 3H2O
Zn + 2HCl --> ZnCl2 + H2
Which group on the Periodic Table most likely contains an element that is highly reactive, a good conductor of electricity, and malleable?
A student hypothesizes that potassium (K) has different chemical properties from calcium (Ca). Which of the following statements best supports the hypothesis?
K has more mass than Ca.
K is a nonmetal, and Ca is a metal.
K and Ca are in the same group.
K & Ca have different valence electrons.
How many energy levels does Xenon have?
How many molecules are in the Chemical formula 3Ca(NO3)2?
When matter changes from a liquid to a gas, it represents a __________ change.
Which element does this Bohr diagram represent?