How many electrons does S2- have, if its atomic number is 16?
18
What's Avogadra's number?
6.0221*10^23 objects
How many Significant Figures are in 22,000? 22,000.?and 22,000.0?
2, 5, and 6
What are the mass numbers of the proton, neutron, & electron respectively?
proton: 1 amu, positive
neutron: 1 amu, neutral
electron: 0 amu, negative
What's an atom with the same number of protons but a different amount of neutrons called?
an isotope
If you have 36.99 grams of oxygen, how many moles of oxygen do you have? The molar mass of oxygen is 15.999
2.312 moles
Name where the three subatomic particles are found in the atom.
protons & neutrons are found in the nucleus. electrons are found in the orbitals
Name at least 3 of the 4 formula units Avogadro's Number can be expressed in.
Particles, atoms, molecules, or just “objects”
How many meters is in 900 nanometers?
9*10-7 meters. Or. 0.0000009 meters.
how do you find the atomic number & mass number of an element?
Atomic #: protons minus neutrons
Mass #: protons plus neutrons
An atom or molecule that's electrically charged is called an ion. What's a positively charged ion called & what is a negatively charged ion called?
Cation (+) and anion (-)
How many kilometers are in 217.2 cm?
0.002172 km or 2.172*10-3 km
Cl-37 has how many neutrons?
20
Name one part of the nuclear theory.
Most of the atom’s mass and all its positive charge are contained in a small core called nucleus
Due to electrons being spaced out within the cloud, most of the volume of an atom is just empty space.
There are many negatively charged electrons outside the nucleus as there are positively charged particles within the nucleus. The atom is electrically neutral.
The speed of light is 3*108 m/s. How fast is the speed of light in nanometers per minute? Use 2 SigFigs
1.8*1019 nm/minutes