Chem Chapter 3
Consider a neutral atom with 30 protons and 34 neutrons. The mass number for this atom is..
64 (Protons+Neutrons= Mass #)
How many electrons are in the second energy level?
8
What is the atomic number of oxygen?
8
T or F: Electrons are found in the nucleus
false
T or F: Neutrons repel each other
false
Where are neutrons found?
nucleus
Where are protons found?
nucleus
The number of neutrons is equal to...
the mass number-atomic number
Atomic number
the number of protons found in the nucleus # of protons= # of electrons
Consider a neutral atom with 30 protons and 34 neutrons. The atomic number of the element is..
30 (Protons=Atomic #)
What charge does a proton have?
+1
What charge does an electron have?
-1
Consider a neutral atom with 30 protons and 34 neutrons. The number of electrons in this atom is
30 (Protons=Neutrons)
How many protons and neutrons are in a neutral atom of Zinc?
30 protons; 35 neutrons
How many neutrons are in Cl?
35.45 (Mass #) - 17 (Atomic #)= 18.45
How many neutrons are in Mg?
12
How many electrons are in the third energy level?
18
How many protons and neutrons are in a neutral atom of argon?
18 protons, 22 neutrons
# of electrons per energy level?
1st-2 2nd-8 3rd-18 4th-32 5th-32 6th-18 7th-8
How many electrons are in the first energy level? (Electron arrangement)
2
What is the electron arrangement for Cl?
2,8,7
What is the electron arrangement for K?
2,8,8,1
How many neutrons are in K?
20
What is the mass number of an atom of potassium that has 20 neutrons?
39
On a mission to a newly discovered planet, an astronaut finds chlorine abundances of 13.85 % for 35Cl and 86.15 % for 37Cl. What is the atomic mass of chlorine for this location? The mass of 35Cl is 34.9700 amu . The mass of 37Cl is 36.9700 amu .
Answer: 36.69 amu Explanation: -Multiply 35Cl's abundance x amu (change percentage to decimal (13.85/100=.1385) .1385 x 34.9700=4.843345 -Repeat process for 37Cl 86.15/100=.8615 .8615 x 36.9700=31.849655 Add the two numbers together: 4.843345+31.849655=36.693 =36.69 amu (4 SF)
Place the following in order of metallic character (greatest to least): Br, Ge, Ca, Ga
Br, Ga, Ge, Ca
T or F: There is 16 electrons in the 3rd energy level?
False, 18
T or F: Protons are attracted to neutrons
False, protons are attracted to electrons protons (+) -----> electrons (-)
Protons+Neutrons=
Mass number
What charge does a neutron have?
No charge: NEUTral
T or F: Proton mass = Neutron mass
True
T or F: Group Number=# of valence electrons
True! Ex: Carbon is in group 4A Hydrogen is in group 1A
Is S larger than Cl?
Yes
