General Chemistry Questions
Where is the Atomic Number on your periodic table?
Above the chemical symbol.
If you are working with Carbon Dioxide or Carbon Monoxide, what division of chemistry are you working in?
Organic Chemistry.
What element has the lightest atoms?
Hydrogen
What is the atomic number?
Number of protons in an element.
What is the degree of error in a 50ml and 100ml graduated cylinder?
nearest ml
What group of people are credited with the beginnings of modern chemistry?
The Alchemists of the 1600s who tried to turn any metal into gold.
If your goal is to create new elements, what division of chemistry are you working in?
Nuclear Chemistry
Can atoms have the same number of neutrons but different numbers of protons? Explain
Yes, you could have isotopes of two different elements.
What is the Mass Number?
Sum of the protons and neutrons.
If you are working with amino acids or proteins, what division of chemistry are you working in ?
Biochemistry.
Where is the atomic mass number on your periodic table?
You have atomic mass on your periodic table below each chemical symbol
If you are working with Iron Oxide (FeO), what division of chemistry are you working in?
Inorganic Chemistry
Look up at Ms Collings. Is what she just did considered chemistry?
Chemistry is the study of materials, including the altering of them. Ripping, crumpling a piece of paper would classify as chemistry.
What are Isotopes?
Atoms of the same element who have different numbers of neutrons.
What did Robert Millikan contribute to chemistry?
Discovered the charge of a single electron. Combined with J.J. Thomson's charge/mass ratio scientists were able to calculate the weight of a single electron.
What is an example of Chemistry causing large scale change throughout human history? Be specific.
Chemistry is altering of materials. Stone Age allowed humans to make better tools and settle instead of being nomads.
Bronze Age allowed even better tools and led to first permanent civilizations.
Iron Age created great political change by sparking more and more wars because of iron weapons.
Microchips made from silicon have created computers, phones, and all sorts of other technology that has greatly altered the world.
If you are trying to figure out which elements are more reactive, have larger atomic nuclei, have higher electronegativity, etc., what division of chemistry are you working in?
Analytical Chemistry
Out of Dalton's four postulates he published with his atomic theory, what is the only one that is not true?
2. All elements of a given element are identical, but different from other elements.
We know now there are Isotopes which are atoms of the same element with different number of neutrons.
What are Significant figures?
All the values you know for certain plus one point of estimation.
How was the AMU established?
Scientists looked at the hydrogen atom and determined it had the lightest atoms and they based the weight of those atoms as the basis for the AMU.
Why is Chemistry often called "The Central Science"?
Chemistry is used in almost all branches of science. At some level almost all economic activity or business will require knowledge of a chemist.
If you are working in thermodynamics or kinetics, what division of chemistry are working in?
Physical Chemistry
Sodium chloride (table salt) is an ionic compound, while oxygen (O₂) is a molecular substance.
a) Describe the type of particles present in each substance (sodium chloride and oxygen).
b) Explain why sodium chloride has a high melting point, but oxygen has a very low melting point.
a) Types of particles
Sodium chloride: It is made of ions – positively charged sodium ions (Na⁺) and negatively charged chloride ions (Cl⁻).
Oxygen (O₂): It is made of molecules, each containing two oxygen atoms covalently bonded.
b) Explanation of melting points
Sodium chloride has a high melting point because the ions are held together by strong ionic bonds in a giant lattice structure. A lot of energy is needed to break these strong attractions.
Oxygen has a low melting point because the molecules are held together by weak intermolecular forces, which require only a small amount of energy to overcome.
Define all three for the points: Proton, Neutron, and Electron.
Proton: Positively charged subatomic particle found within the nucleus.
Neutron: Subatomic particle with no charge that is found within the nucleus.
Electron: Negatively charged particle with no charge that is found outside the nucleus.
Look up to the board at Ms Collings' drawing. Describe the archers shooting pattern correctly using the correct terms.
The archer is both precise/reliable and accurate/valid since the pattern is all in the bullseye.