A phosphorus-31 atom has ___ protons, neutrons, and __ electrons.
15; 16; 15
Which of the following is an alkali metal?
Rb
What are cathode rays?
Electrons
Which statement regarding Millikan’s oil drop experiment is true?
The rate at which charged oil droplets fell in an adjustable electric field was related to the charge on an electron.
Which of the following statements is TRUE:
a) The different Isotopes of an element are not always equally abundant.
b) The identity of an isotope can be determined solely by its mass
c) Isotopes of an element contain the same number of neutrons but different numbers of protons
d) Atoms of different elements cannot contain the same number of neutrons
e) Atoms of different elements can have the same atomic numbers
A
Which of the following statements is true regarding Thomson’s cathode ray experiment and the discovery of electrons?
The charge of the electron was determined.
What is the symbol for magnesium?
Mg
Who discovered electrons?
Joseph John Thomson
What is the symbol for potassium?
K
Cs is the symbol for.
Cesium
Elements 21 through 30 are known as
Transition metals
Which of the following is NOT true regarding cations and anions?
An oxygen molecule can lose an electron to form O-2
Which statement regarding Rutherford’s gold-foil experiment is TRUE?
The results suggested the positive charge of an atom is localized in a small regions.
A 35/17 Cl atom has ___ protons, ____ neutrons, and _____ electrons.
17; 18; 17
Which statement regarding Rutherford’s nuclear model of the atom is TRUE?
The atom is mostly empty space
Who was the first scientist to determine the charge of an electron?
Robert Millikan
A 16/8 O 2- ion has ___ protons, ____ neutrons, and ____ electrons.
8; 8; 8
Which two elements would you expect to show the most similar behavior?
Ca and Sr
All atoms of a particular element have the same number of…
Protons
Which subatomic particles have opposite charges?
Protons and electrons
The 12/6 C nucleus is an example of
An element
Which subatomic particles have approximately equal masses?
Protons and neutrons
12/6 C and 13/6 C are examples of…
Isotopes
Protons and neutrons are examples of …
Nucleons
Isotopes have the same…
Number protons but different number neutrons
A common pain-relieving medication contains acetaminophen and codeine. If a 1.5g tablet contains 0.30g acetaminophen (C8H9NO2, 151.16 g/mol) and 0.044g codeine (C18H21NO3, 299.36 g/mol) , calculate the number of moles of acetaminophen in the tablet.
2.0 × 10^-3 mol
Which is the correct symbol for an isotope that contains 33 protons, 33 electrons, and 42 neutrons
75/33 As
The average atomic mass of nickel is 58.693u. Given the data in the following table, what is the natural abundance of nickel-64?
0.9256%
Which has the highest molecular mass?
CBr4
What is the correct symbol for an electron?
0/-1 e
How many CaCl2 formula units are in 125u of calcium chloride?
1.13 formula units
What is the formula unit mass of ammonium carbonate ((NH4)2CO3)?
One isotope makes up to 97% of all calcium atoms. Which one is it?
40Ca
Which of the following compounds contains the most nitrogen atoms per formula unit?
C8H12N4O3
How many gold atoms are there in a 1.00 kg bar of gold?
3.06 × 10^24
What is the correct symbol for an alpha particle?
4/2a
What is the mass if 4.76 × 10^20 molecules of the hydrogen octane (C8H18)
0.0903g
A popular recipe for chocolate chip cookies requires 4.6g of baking soda (NaHCO3). How many moles of baking soda are required for this recipe?
0.055 mol