The video tutorial covers the basics of Bohr and Lewis dot models, focusing on the importance of valence electrons in predicting atom reactivity and bonding. It explains how to determine the number of valence electrons using the periodic table, highlighting group characteristics and exceptions like helium. The tutorial provides step-by-step instructions on drawing Lewis dot structures for various elements, emphasizing the significance of valence electrons in chemical reactions.

What do Bohr models show that Lewis dot structures do not?

• Chemical bonds

• Only valence electrons

• Protons and neutrons

• Atomic mass

Why are valence electrons important?

• They help predict an atom's reactivity and bonding

• They are the same for all elements

• They determine the atomic mass

• They are found in the nucleus

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How many valence electrons do elements in the first column of the periodic table have?

• Two

• Three

• One

• Four

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Which group of elements has an unpredictable number of valence electrons in this class?

• Group 1

• Group 2

• Group 18

• Transition metals

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How many valence electrons does sulfur have?

• Eight

• Six

• Four

• Two

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Why is helium placed in group 18 despite having only two valence electrons?

• It has a full outer shell

• It is a metal

• It has eight protons

• It is highly reactive

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What is the mnemonic to remember the number of valence electrons?

• One, two, three, four, five, six, seven, eight

• One, two, three, four, five, six, seven, eight, nine

• One, two, skip a few, three, four, five, six, seven, eight

• One, two, three, skip a few, four, five, six, seven, eight

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How many valence electrons does lithium have?

• Two

• Three

• Four

• One

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What is the chemical symbol for calcium?

• Ca

• C

• Cl

• Cu

How many valence electrons does phosphorus have?

• Three

• Six

• Four

• Five

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