name stuff
Ca3N2
what's my name?
calcium nitride
draw a beaker and a flask and label each
beaker = cylindrical
flask = triangle shaped base
define half life
the amount of time it takes for a radioactive substance to become HALF as radioactive
what is the molar mass of CaCO3?
100.09g/mol
how many moles are there in 32g of oxygen?
2 mol!
What is the real name for H2O?
dihydrogen monoxide
draw an example of one chemical change and one physical change that happens in a kitchen
physical ex: cutting an onion
chemical ex: toasting a piece of bread
define the difference between ionic bond and covalent bond
ionic = electrons taken by more electronegative atom
covalent = electrons shared between atoms
Figure out how many electrons are being shared between P2
6!
breaking this lab procedure has lead to serious injuries in many chemistry classes (name 3)
- not wearing goggles
- baggy clothes over heat source
- hair not tied back
- sitting at a lab station
- not following directions step by step
- drinking / eating at lab station or out of glassware
what is the formula for copper (II) sulfate?
CuSO4
write 49843120001 in scientific notation with two sig figs
5.0 x 1010
define polar bond
Electrons are not evenly distributed or shared within a molecule. The electrons will be drawn to the more electronegative elements, causing one side of the molecule to have a negative charge, and the other side positive (like a magnet!)
What is the percent composition of water in Magnesium sulfate heptahydrate
51.2%
this will cause a trigonal planar molecule to become trigonal pyramidial
lone pairs on the central atom
What is the name of the polyatomic ion in this compound?
CuC2H3O2
acetate
write a number with 8 sig figs that is smaller than 1.0.
0.0000001
define molar mass
Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol). It is calculated by summing the atomic masses of all the atoms in a molecule's formula.
An isotope has a half-life of 10 years. If 1.0g of the isotope disintegrates over a period of 30 years, how many grams of Cs-137 would remain?
0.125g
Is sugar polar or nonpolar? How do you know?
polar - like dissolves like (sugar dissolves in water)
name the molecular shape of silicon tetrachloride
tetrahedral
draw the lewis structure for CF3S
polar tetrahedral
define aqueous AND precipitate
Aqueous = water solvent with substance dissolved within it
In an aqueous solution, precipitation is the "sedimentation of a solid material from a liquid solution". The solid formed is called the precipitate.
Find the empirical formula for this substance
40.0% carbon
6.7% hydrogen
53.3% oxygen
CH2O
Salhusium has four naturally occurring isotopes. Salhus-26, Salhus-27, Salhus-28 and Salhus-29. Why is the average atomic mass of Salhusium 26.1 amu?
the vast majority of Salhusium isotopes are
Salhus-26
because it's the most stable