Atomic Structure
What is the atomic number for chromium (Cr)?
24
What type of matter is chlorine (Cl) gas?
physical
D=mass/volume
What type of elements make ionic compounds?
Metal and nonmetal
What does atomic number tell you?
The number of protons.
heterogeneous mixture
chemical
What are the two sets of units for density?
g/ml or g/cm3
Metals always are _____ charges and nonmetals are always ______ charges.
metals = positive
nonmetals = negative
How many neutrons does cobalt (Co) have?
32
Homogeneous - uniform, looks like 1 thing
Heterogeneous - not uniform, can see multiple components and pieces
What type of change is dissolving sugar in coffee?
physical
1.189 g/ml
What is the name of RaCl2?
radium chloride
neutrons = atomic mass - protons
What is the difference between element and compound?
element - 1 type of atom
compound - many types of atoms
Describe two physical changes that can happen to a rod of iron.
answers may vary (melt, cut, bend, paint)
A piece of copper has a density of 8.92 g/cm3 and measures 4.00 cm long, 2.00 cm high, and 1.00 cm thick. What is the mass in grams of the piece of copper?
V=l*w*h
71.4 grams
What is the name of FrI?
Francium iodide
What makes atomic mass?
protons & neutrons
If you have a bucket with sand and ocean water (salt and water) describe a way you can separate all 3 components.
Filter - separates sand from salt water
evaporation - separates water from salt
Describe a chemical change that can happen to iron.
answers may vary (rust, oxidize, acid)
Water has a density of 1.00 g/ml. Sodium has a density of 0.97 g/ml and magnesium has a density of 1.74 g/ml. Which substance will float in water?
sodium
What is the formula for calcium phosphide?
Ca3P2