Lab

Question 1

physical properties of elements

Metals

Answer 1

• usually shiny or have a metallic luster
• good conductors of heat and electricity
• ductile (can be drawn into a wire)
• malleable (can be molded into a shape)
• if cut can see fresh shiny metal underneath

Question 2

physical properties of Na and Ca and why? - metal

Answer 2

• some such as Na and Ca may have a white coating of oxide formed by reacting with O2 in air

Question 2

Physical property of nonmetals

Answer 2

• not good conductors of heat and electricity
• brittle (not ductile)
• appear dull
• not shiny

Question 3

Periodic Table

- horizontal rows

Answer 3

periods

Question 4

periodic table

vertical columns

Answer 4

groups

Question 5

groups of periodic table

Answer 5

• contains elements that have similar physical and chemical properties
• numbered across the top of the chart

Question 6

elements in group 1

Answer 6

alkali metals

Question 7

elements in group 2

Answer 7

alkaline earth

Question 8

elements in group 7

Answer 8

halogens

Question 9

elements in group 8

Answer 9

noble gases

- elements not very reactive compared to other elements

Question 10

dark zigzag line that looks like a staircase in periodic table

Answer 10

• separates the metals on the left side from the nonmetals on the right side

Question 11

subatomic particles

Answer 11

• (there are different kind of atoms for each of the elements)
• atoms are made up of smaller bits of matter called subatomic particles

Question 12

protons

Answer 12

possitively charged particles

Question 13

electrons

Answer 13

negatively charged particles

- so small their mass is considered to be negligible compared to the mass of proton or neutron

Question 14

neutrons

Answer 14

neutral (no charge) particles

Question 15

nucleus

Answer 15

• in an atom, the protons and neutrons are tightly packed in the tiny center called necleus

Question 16

atoms

Answer 16

• most of atom is empty space, contains fast-moving electrons

Question 17

atomic number

Answer 17

equal to number of protons

Z = p+ = e-

Question 18

mass number of an atom

Answer 18

protons + neutronsº

Question 19

isotopes

Answer 19

atoms of the same element that differ in the number of neutrons
- have the same number of protons, but different mass numbers

Question 20

complete symbol of an isotope

Answer 20

mass number (p+ and nº) ->  34
symbol of element ---------->   S
atomic number (p+) --------> 16

Question 21

Dmitri Mendeleev

Answer 21

found that the chemical properties of elements tended to recur when the elements were arranged in order of increasing atomic mass

Question 22

repetition of similar characteristic is called?

Answer 22

periodic behavior

Question 23

valence electron

Answer 23

• electrons in the highest or outermost energy level
• determine chemical properties of the elements
• if elements are grouped according to number of valence electrons - chemical and physical properties are similar