G6_Ch4+Review

GRADE 6 – REVIEW - TEST CHAPTER 4 - ** Answers **

1. The small, negatively charged particles discovered by J.J. Thomson are called __** ELECTRONS **_ .__

2. Constructing a ** MODEL **_____would be most useful for describing atoms.

3. What group, on the periodic table contains elements that are gases at room temperature? __** THE NONMETALS **__

4. The atomic number of manganese is 25; its mass number is 55. How many neutrons does an atom of manganese have in its nucleus? __** 30 **__

5. An element's atomic number is the number o__f _** PROTONS **_ i__n the nucleus of each atom of that element.

6. Rutherford called the positively charged, central part of the atom the ___** NUCLEUS **__.

7. What is the difference between a mixture and a compound? In a mixture, the substances can be easily separated (filter, sift, etc.). In a compound, the elements that make up the compound cannot be easily separated. A large amount of energy is required to divide a compound into its original elements.

8. What are the major characteristics of most metals? a. Shiny luster b. Good conductors of heat and electricity c. Most are solids at room temperature d. Malleable, or can be shaped e. Ductile, or can be drawn into wire without breaking 9. Atoms of the same element that have different numbers of neutrons are called __** ISOTOPES **__.

10.Democritus believed that the universe was made of empty space and _** ATOMS **_.

11.A(n) __** ELEMENT **___ is a material that cannot be broken down into simpler materials by ordinary means.

12.Scientists have broken down protons and neutrons into smaller particles called ** QUARKS **_.

13.An example of a synthetic element is __(** ANY ELEMENT OVER 93 **)_ .__

14.The atomic mass of an element is ** AVERAGE MASS **_ of that element.

15.What nineteenth century scientist designed the atomic theory of matter? ** DALTON **

16.An atom containing six positive charges and six negative charges has _** NO ** charge.

17.The ** PERIODIC TABLE **_ is a chart created by chemists to organize the elements.

18.James Chadwick named the uncharged particles in the atomic nucleus __** NEUTRON **_ .__

19.On an “element key”, where is the atomic mass located? __** UNDER THE ELEMENT’S NAME **__

20.According to the periodic table, how many electrons does an atom of krypton have? __** 36 **__

21.What is the same for two atoms of the same element that are isotopes? __** THE NUMBER OF PROTONS **__

22.What part or parts of an atom accounts for most of its mass? __** THE NUCLEUS **__

23.What is the mass number of an atom that has 2 protons and 3 neutrons? __** 5 **__

24.How can most of the elements on the periodic table be classified? __** METALS **__

25.What do we call molecules that come together without bonding? __** MIXTURE **__

26.Mendeleev arranged families of elements ** IN GROUPS FROM LEFT TO RIGHT ** in his periodic table.

27.From left to right, what is the order of zones on a periodic table? 28.According to the periodic table, iodine will have similar chemical and physical properties to which elements? ** FLUORINE, CHLORINE, BROMINE AND ASTATINE ** 29. Which gas is a noble gas? Any of the following is correct:
 * METALS, METALOIDS, NON-METALS **
 * HELIUM, NEON, ARGON, KRYPTON, XENON, RADON **

30.The _** ELEMENT **_ ** KEY **_ contains the name, atomic number, symbol, and atomic mass of an element.

31.Hydrogen is a __** GAS **___ at room temperature?

32.A(n) ** GROUP **_ of elements on the modern periodic table contains elements with similar chemical and physical properties.

33.What are some common properties of nonmetals? a .Dull in appearance b.Poor conductors of heat and electricity c.Many are gases at room temperature d.Brittle, cannot change shape without breaking