Atoms, Elements & Compounds
Atoms are made of what smaller particles? Name the charges of each of these particles.
Protons +
Neutrons 0
Electrons -
What is the range of the pH scale? Which numbers represent acids, bases, and neutral solutions?
-Acids: 0-6
-Bases: 8-14
-Neutral: 7
What is the shape of a DNA molecule?
Double Helix
What is an ingredient added to a food item (often for colouring, preserving, or texturing purposes) called?
An additive
What are two overarching categories of waves, based on their movement?
Transverse Waves and Longitudinal Waves
If an atom of Calcium loses 2 electrons, what is its new charge?
+2
What are two variables that affect the rate of a chemical reaction?
- Concentration
- Temperature
- Surface area
When does DNA need to replicate itself?
Before any type of cell division
Salts
Nitrates
Acids
Alcohols
Sugars
In visible light, which colours have the highest and lowest frequencies? Explain what that means.
Lowest Frequency = Red light (longer wavelengths)
Highest Frequency = Violet light (shorter wavelengths)
Name 3 properties of Alkali Metals
-Highly Reactive
-Solid
-Soft
-Shiny
After burning 12g of coal, there is 5g of ash left over. Assuming ash and carbon dioxide are the only products, what mass of CO2 was produced, and how do you know?
7g of CO2 were produced; matter can neither be created nor destroyed according to the law of conservation of mass.
What are 2 types of genetic technologies, and how do they help people around the world?
-Genetic Engineering of foods or animals
-Cloning
-Gene Therapy
Based on our class's experiments, which category of preservatives perform best against E. coli?
Acids
300,000,000 m/s
3x108 m/s
If an atom of Calcium loses 2 electrons, how many valence electrons does it now have?
8
A student collected 32 mL OF CO2 from a neutralisation reaction in 50 section. What is the reaction rate?
32/50 = 0.64 mL/s
Assuming eye colour is coded by one gene, what is the probability of getting a blue-eyed offspring if a homozygous blue-eyed person has kids with a heterozygous brown-eyed person? Show your work.
50%
What are 3 important reasons that people use preservatives?
- Prevent food decay
- Prevent food-borne illnesses
- Allow foods to be transported long distances
-Enable foods to be eaten out of season
How does the type of medium impact the speed of sound waves? Give examples.
The denser the medium (ie rock), the faster sound waves travel. The less dense the medium (ie air), the slower sound waves travel.
Covalent Bond
-they are both nonmetals
-they have the same pull on valence electrons, so the valence electrons will be shared in the middle
Balance the chemical equation below:
KMnO4 + HCl → KCl + MnCl2 + H2O + Cl2
2KMnO4 + 16HCl → 2KCl + 2MnCl2 + 8H2O + 5Cl2
How can a random mutation in an individual lead to the evolution of a species?
-If the mutation is advantageous, the organism will survive to pass on its DNA
-Its offspring are more likely to have that mutation, which, if advantageous, will help them survive and pass on their DNA
Why should sulphates and nitrates be avoided as preservatives when possible?
They are carcinogens (linked to cancer)
If an electromagnetic wave has a wavelength of 10m, what is its frequency and what type of wave is it?
3 x 107 Hz or 30,000,000 Hz
Radio Wave