Basics
Measurement
Density/Temperature/ Percent Error
Atomic Models
Periodic Table/ Subatomic Particles
100
Name two of the steps in the scientific method.
Observations, Hypothesis, Experiments, Theory
100
What is the difference between qualitative and quantitative?
Qualitative – description in words Quantitative – uses a number
100
What is the density of an object with mass=12.5 g and volume=4.3 mL?
2.9 g/mL
100
What is an atom?
Smallest part of an element that still has all the properties of that element
100
What are the rows of the periodic table called? What are the columns called?
Rows – periods Columns – groups/families
200
What is the difference between a physical and chemical change?
Physical - the material doesn't change to something else, just some properties change. Chemical - the material changes into a new substance.
200
What is an accurate measurement?
Measurement that comes close to the actual or true value of whatever is measured
200
What is the mass of an object with volume = 5.6 mL and density = 12 g/mL?
6.7 x 10^1 g
200
What did Thompson’s atomic model look like?
Plum pudding – lump of protons (positive charge) with electrons (negative) mixed in.
200
What are the group A elements all called? Group B elements?
Group A - Representative elements Group B – Transition metals
300
What is the difference between the arrangement and movement of atoms in solids, liquids, and gases?
Gas- particles are far apart moving rapidly Liquids - particles near each other, moving slightly (more than in solids) Solids - particles packed together, slightly shaking
300
What is a precise measurement?
A measurement that is close to a series of other measurements.
300
If you find the temperature to be 500 K what is the temperature in celcius?
227°C
300
Who’s experiment gave evidence of an atomic nucleus?
Rutherford
300
What are the charges on protons, neutrons, and electrons?
Protons 1+ Electrons 1- Neutrons 0 (neutral)
400
What is the difference between a homogeneous mixture and a heterogeneous mixture?
Homogeneous - same throughout heterogeneous - not uniform throughout
400
Which measurements have unlimited/undefined number of sig figs?
Conversions and counted items
400
What is the volume of an object with mass = 15 g and density = 2.5 g/mL?
6.0 mL
400
What did Bohr’s atomic model look like?
Planetary model – electrons follow fixed paths around the nucleus
400
How do you find the atomic number?
The number of protons in the atom
500
What are the five types of chemistry?
Physical, Organic, Inorganic, Analytical, Biochemistry
500
What is the difference between calculating sig figs in addition/subtraction versus multiplication/division?
Addition/subtraction – left most decimal place Multiplication/division – total number of sig figs
500
An experimental measurement was taken of 10.4 mL and the actual measurement was 9.7 mL. What is the percent error?
7.2%
500
Who’s atomic model describes an electron cloud? (model we use today)
Schrodinger
500
How do you find the mass number?
The number of protons plus neutrons
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