CHEMISTRY CENTRAL
This science studies matter, its properties, its composition, and the changes it undergoes.
What is chemistry?
This is the lowest layer of Earth's atmosphere and the layer where humans live.
What is the troposphere?
The basic SI unit used to measure length is this.
What is the meter (m)?
How many significant figures are in:
25.7
What is 3?
Complete this relationship:
1m=____cm
What is 100 cm?
Anything that has mass and occupies space is called this.
What is matter?
Most of Earth's protective ozone layer is located in this atmospheric layer.
What is the stratosphere?
A balance shows:
1002.400 g
How many significant figures does this number possess?
What is 7?
How many significant figures are in:
0.00450
What is 3?
Convert:
250cm→m
What conversion factor is needed
Solution: 2.50 m
1m/ 100 cm
Chemistry is sometimes called the central science because it connects physical sciences with these other major fields of science
What are biology, physics, environmental science, medicine, and Earth science?
Clouds, rain, thunderstorms, hurricanes, and most other weather occur in this atmospheric layer.
What is the troposphere?
Identify the quantity represented by each unit:
g, mL, °C
g = mass
mL = volume
°C = temperature
Round 18.3764 to three decimal places.
What is 18.376?
Convert:
3.5kg→g What conversion factor is needed?
What is 3500 g
What is 1000g/1kg
A doctor studying how a medication reacts with molecules inside the human body demonstrates the connection between chemistry and this science.
What is biology/medicine?
These chlorine-containing compounds, once widely used in refrigerators and aerosol products, contributed greatly to stratospheric ozone depletion.
What are chlorofluorocarbons, or CFCs?
35 degrees Fahrenheit converted to Kelvin is?
274.7K?
Calculate and give the answer using the correct number of decimal places:
12.45 + 3.2 + 0.678
What is 16.3?
12.45 + 3.2 + 0.678 = 16.328
A patient drinks 2.5 L of water. Convert this volume to mL using dimensional analysis.
2.5L×1L/1000mL=2500mL
Imagine that knowledge of chemistry suddenly disappeared. Name three areas of everyday life that would be seriously affected and explain why.
Any of the following or similar suitable:
Medicine and pharmaceuticals, Agriculture and fertilizers, Food production and preservation, Water purification, Cleaning products, Fuels and energy, Batteries, Plastics and synthetic materials, Cosmetics, Environmental monitoring, Construction materials, Electronics
Stratospheric ozone is considered “good ozone,” while ground-level ozone is considered “bad ozone.” Explain why.
Stratospheric ozone protects living organisms by absorbing harmful ultraviolet radiation from the Sun.
Ground-level or tropospheric ozone is an air pollutant that contributes to smog and can damage lungs, plants, and other organisms.
The answer to the sum and a multiplication below are:
21.567 + 1.89 - 2.5 =
22.5 x 2.3 =
21.0....(1 dp)
52.....(2sf)
Calculate and report the answer with the correct number of significant figures:
4.56×2.1
What is 9.6?
Calculation:
4.56×2.1=9.576
4.56 → 3 significant figures
2.1 → 2 significant figures
The answer must therefore have 2 significant figures.
A car travels 72.0 kilometers per hour. Convert this speed to meters per second.
What conversion factors do you need?
What are:
1km/1000m
1hr/3600s
What is:
20.0 m/s