Let's keep it simple!
What are the fundamental SI units for:
Mass
Length
Time
Temperature
Mass = Kilograms
Length = meter
Time = second
Temperature = Kelvin
How many elements are there in the periodic table? And what is the lightest element?
There are 118 elements.
The lightest element is Hydrogen.
When an atom loses electrons, the # of electrons decreases while the # of protons in the nucleus remains the same. We call this a ______
When an atom gains electrons, the # of electrons increases while the # of protons in the nucleus remains the same. We call this a ______
cation, ion with a positive charge
anion, ion with a negative charge.
What is the hardest known natural material?
Diamonds.
How many bones are there in the human body?
There are 206 bones.
What is the scientific notation for the following prefixes:
micro
milli
centi
pico
micro =10-6
milli = 10-3
centi =10-2
pico =10-12
What is the boiling point of water in degrees celcius?
100◦C
What are diatomic molecules? Give examples
Diatomic molecules are molecules made up of two or more atoms. O2, N2, H2.
All elemental forms of Group 7, the halogen family contain diatomic molecules.
Which of these elements is a nonmetal?
Manganese
Sulfur
Aluminum
Beryllium
Sulfur
Planet Earth is surrounded by different layers of gas, which when taken together we call the...?
Atmosphere.
What is the difference between accuracy and precision?
Accuracy refers to the agreement of a particular value with the true value.
Precision refers to the agreement among several measurements of the same quantity.
A chemist, finds that 25.00cm3 of Isopropyl alcohol has a mass of 19.625g at 20◦C. Calculate the density of this substance.
Density = mass/density
Density = 19.625g/25.00cm3 = 0.7850g/cm3
There are only two elements that are liquid in their elemental forms at room temperature. Which elements are these?
The non-metal bromine (containing Br2 molecules)and the metal mercury.
The metals Gallium and Cesium almost qualify in this category; they are solids at 25℃, but they both melt at ~ 30℃.
Mention 6 nonmetal elements
Mention 6 noble gases
Nonmetals: H, C, N, O, P, S,
Noble gases: He, Ne, Ar, Kr, Xe, Rn
Dolly was the first ever living creature to be cloned. What type of animal was she?
Sheep
Three of the most common states of matter are solid, liquid and gas. A liquid has:
A defined volume, but not a defined shape, it takes the shape of its container.
How do we classify the periodic table?
We classify it in groups (families) columns 1-18 or 1A-8A and periods (rows) Ex/ H and He belong to the first period. Then we further classify it by:
Alkali metals
alkaline earth metals
Nonmetals
halogens
noble gases
metalloids
What are allotropes? Give examples
Different physical forms of a given element are called allotropes.
The 3 allotropes of solid carbon are: diamond, graphite and a more recent discovery buckminsterfullerene. They all have different properties.
Discovered by Alexander Fleming, this is now used to treat infections and it is considered one of the most important discoveries in the field of medical science, What is it?
Penicillin.
The Nobel Prize is one of the most prestigious awards in the field of science. The man behind this award is Alfred Nobel, what did he invent?
Dynamite.
Give three example of physical properties and three examples of chemical properties.
Physical: Boiling point, freezing point, metal wire conducts electricity, diamonds are hard, etc.
Chemical: sugar ferments to form alcohol, a metal rusts, wood burning gives off heat and gases leaving ashes behind, digestion of food, growth of a plant, etc.
Who is credited with the invention of the modern periodic table?
a) Nobel
b) Lavoisier
c) Mendeleev
d) Mendel
c) Mendeleev is credited with creating the modern periodic table, although his table was based on increasing atomic mass rather than atomic number. Mendeleev's table grouped elements according to common properties and periodic trends.
You can't live without iron. Where in the body is most of the iron located?
Your blood. Most of the iron is locked up in the hemoglobin found in red blood cells, used for oxygen transport.
The symbol Sb stands for stibium or stibnite. What is the modern name of this element?
Antimony. Stibium is the old name for antimony. From the Greek anti + monos for " not alone". Don't confuse it with the symbol Sn for Tin, which is safe enough to use to make cans for food. Antimony and most of its compounds are toxic.
A penny is mostly made from what type of metal?
Mostly made out of Zinc and covered in copper.