Their stability increases and their energy decreases
4. What group of elements have a stable octet in their natural state?
5. All salts are held together by what type of bonds?
6. List 3 some properties that all salts share.
Salts are hard, dissolve in water and do conduct electricity in a liquid form.
7. List some differences between metals and salts.
Metals are soft, have mobile electrons and conduct electricity in solid form.
Salts are hard, have mobile ions in a liquid form and conduct electricity only in liquid and solution form.
8. Explain how metallic bonding gives metals their unique properties.
Because metals have mobile electrons.
9. Describe how covalent and ionic bonds differ with regard to melting point, boiling point, and bond strength.
Covalent bond: low melting point and boiling point and weak bond
Ionic bond: high melting point and boiling point and strong bond.
10. Explain the difference between polar covalent and nonpolar covalent bonds.
Polar covalent: two nonmetals share electrons unequally
Nonpolar covalent: two nonmetals share electrons equally
1) Explain why beryllium loses electrons when forming ionic bonds, while sulfur gains electrons.
Beryllium has only two valence electrons and sulfur has 6 valence electrons and high electronegativity. Sulfur will gain two electrons from beryllium, so both elements will have 8 valence electrons and become stable.
2) Explain why fluorine and chlorine have similar reactivities (the word “valence” should be somewhere in your answer!)
They have the same # of valence electrons (same group)
3) Explain why oxygen is a fairly reactive element while neon is not.
Oxygen has 6 valence electrons and needs two to become stable. So, oxygen will have to share or steal electrons from other elements (reactive). Neon is stable because it has 8 valence electrons.
4) You have been given a substance in an unmarked beaker in the chemistry laboratory and asked to determine if it is an ionic compound or not. You tap the crystals gently and they shatter but still retain their sharp edges. You heat the substance gently at first and then harder and after two to three minutes of heating it does not melt. It dissolves in water and the water solution conducts electricity. Is the substance an ionic or a covalent compound? Explain
It is an ionic compound because ionic compounds are hard, have high melting points, dissolves in water and conduct electricity in solution.