Which general statement does NOT apply to metals?

21. Which general statement does NOT apply to metals? (1 point)

Most metals are ductile.

Most metals are malleable.

Most metals are brittle.

Most metals are good conductors of electric current.

22. Among the alkali metals, the tendency to react with other substances (1 point)

does not vary among the members of the group.

increases from top to bottom within the group.

varies in an unpredictable way within the group.

decreases from top to bottom within the group.

23. Study the electron dot diagrams for lithium, carbon, fluorine, and neon in Figure 6-1. Choose the statement that correctly identifies the most stable of the elements.

Lithium is the most stable element because it has to lose only one electron to achieve a stable configuration.

Carbon is the most stable element because it can form four bonds.

Fluorine is the most stable element because it has to gain only one electron to achieve a stable configuration.

Neon is the most stable element because its highest occupied energy level is filled.

24. The formation of an ionic bond involves the

transfer of electrons.

transfer of neutrons.

transfer of protons.

sharing of electrons.

25. In a polar covalent bond,

electrons are shared equally between atoms.

a cation is bonded to an anion.

electrons are transferred between atoms.

electrons are not shared equally between atoms.

26. Beryllium, Be, and chlorine, Cl, form a binary ionic compound with a one-to-two ratio of beryllium ions to chloride ions. The formula for the compound is

Be2Cl.

BeCl.

BeCl2.

Be2Cl2.

27. double-replacement and decomposition

28. In terms of energy, how would you classify the following chemical reaction?

2Cu + O2 -> 2CuO + 315 kJ

endothermic

exothermic

both endothermic and exothermic

neither endothermic nor exothermic

29. A log is burning in a fireplace. If the amount of oxygen reaching the log is decreased, which of the following statements is true?

The reaction rate increases.

The reaction rate decreases.

The reaction rate remains the same.

The reaction rate depends only on the temperature.

30. A student dissolved equal amounts of salt in equal amounts of warm water, room-temperature water, and ice water. Which of the following is true?

The salt dissolved most quickly in the warm water.

The salt dissolved most quickly in the room-temperature water.

The salt dissolved most quickly in the ice water.

none of the above

31. A solution that contains more solute than it would normally hold at that temperature is said to be

saturated.

unsaturated.

supersaturated.

concentrated.

32. Which of the following is NOT a property of an acid?

tastes sour

usually reacts with a metal

changes the color of an indicator

feels slippery

33. A base is defined as a compound that produces

hydroxide ions in solution.

hydrogen ions in solution.

hydronium ions in solution.

sodium ions in solution.

34. stay about the same.

35. Uranium-238 undergoes alpha decay. Therefore, uranium-238 will

remain stable.

36. What type of radiation is emitted when polonium-212 forms lead-208?

an alpha particle

a beta particle

gamma radiation

all of the above

37. Transmutation involves

nuclear change.

chemical change.

both a nuclear change and a chemical change.

neither a nuclear nor a chemical change.

38. During nuclear fission, great amounts of energy are produced from

very small amounts of mass.

tremendous amounts of mass.

a series of chemical reactions.

particle accelerators.

39. Which of the following conversion factors would you use to change 18 kilometers to meters?

1000 m/1 km

1 km/1000 m

100 m/1 km

1 km/100 m

40. the ratio of their masses is always the same.

41. Which of the following provides the best analogy for an electron in an atomic orbital?

a cow grazing in a pasture

a bird resting on a tree branch

an ant crawling on the surface of a leaf

a bee hovering around a bee hive

42. The tendency of an element to react is closely related to

its atomic mass.

attractions between its atoms.

the number of valence electrons in atoms of the element.

the ratio of protons to neutrons in atoms of the element.

21. Most metals are brittle

22. Increases from top to bottom within the group.

23. Neon is the most stable element because its highest occupied energy level is filled.

24. transfer of electrons.

25. electrons are not shared equally between atoms

26. BeCl2

27. double-replacement and decomposition

28. exothermic

29. The reaction rate decreases.

30. The salt dissolved most quickly in the warm water

31. Saturated

32. feels slippery

33. hydroxide ions in solution.

34. stay about the same.

35-40: I do not know.

41. a bee hovering around a bee hive

42. the number of valence electrons in atoms of the element.