Stoichiometry
When magnesium reacts with oxygen, magnesium oxide is produced.
If 12 g of magnesium reacts to produce 20 g of magnesium oxide, calculate the mass of oxygen that reacted.
8g
Name the force that impedes moving objects
Friction
How many chromosomes does a human gamete contain
23
What does the frequency of a sound wave determine?
Pitch
Identify the group in the Periodic Table whose elements are chemically inert under normal conditions
Noble gases
Magnesium reacts with chlorine to form magnesium chloride.
If 24 g of magnesium reacts completely with chlorine, calculate the mass of chlorine needed.
Given:
71g
A stationary block of 5kg rests on a horizontal ground.A force of 30N is exerted on the block vertically.What is the force experienced by the ground?
80N
State a difference between a prokaryotic and eukaryotic cell
Prokaryotic Cells:
Reverse arguments accepted
State whether True or False: Ultraviolet radiation have a higher frequency than Infrared red radiation
True
Magnesium is in group 2 of the periodic table.Will it form an anion or cation when reacting?
Cation
Element X has three naturally occurring isotopes.
Calculate the relative atomic mass (Aᵣ) of element X.
231.8
A vehicle has a weight of 5525 N and an acceleration of 2.5 m/s2. What is the force acting on the vehicle?
1.4 × 10³ N
1381.25 and 1409 and all close values are accepted
Which cells in leaves do most of the photosynthesis occur in? State one adaptation they have for their function
Palisade mesophyll cells
Long and column shaped
Many chloroplasts
Thin cell walls
Close to upper surface of leaves
Large vacoule
A wave has a frequency of 6.0 × 10¹⁴ Hz and a wavelength of 500 nm. Calculate the speed of the wave. Give your answer in m/s.
3*10^8
An element that forms X³⁻ — which group does it belong to?
Group V
25.0 cm³ of a sodium hydroxide solution is completely neutralised by 20.0 cm³ of 0.200 mol/dm³ hydrochloric acid.
Calculate the concentration of the sodium hydroxide solution in mol/dm³.
0.16 mol/dm3
A 100g mass is suspended from a spring next to a vertical metre ruler, using a clamp and stand.The top of the spring is level with the 0.0 cm mark. The bottom of the spring is level with the 27.2 cm mark.
The 100g mass is replaced with a 600g mass. The length of the spring is now 89.7 cm. The spring has not reached the limit of proportionality.
The 600g mass is replaced with a 200g mass. What is the length of the spring?
39.7cm
State an organ that has cells which produce enzymes as well as cells which produce hormones.
Pancreas
Two men stand a fixed distance away from a wall. One of them hits two bricks against each other, causing a loud sound. While the other starts a stopwatch as soon as the sound is heard. A stopwatch shows the time taken to be 9 seconds and 700 milliseconds. Determine the approximate distance between the two men and the wall.
As you go down group 7, what happens to the reactivity and to the melting points of the elements?
Reactivity reduces
Melting point increases
Magnesium reacts with hydrochloric acid:
A student adds 3.0 g of magnesium to 40.0 cm³ of 2.0 mol/dm³ hydrochloric acid. Calculate the volume of hydrogen gas produced at RTP
Given:
0.96dm3
Two people, X and Y, sit on a seesaw. Person X sits 1.5 m to the left of the pivot and exerts a downward force of 400 N. The seesaw itself has a weight of 300 N, which acts through the pivot. When the seesaw is balanced, the pivot pushes upwards with a force of 900 N.
Determine:
200N
3m
Which organelle in bacteria is removed and used typically for genetic modification?State one application of it.
Plasmids
More vitamins in food
Insulin production
Resistance to pests by plants
A water wave travels from deep water into shallow water. In deep water, the wavelength is 12 cm and the frequency is 5.0 Hz. In shallow water, the speed of the wave is reduced to 0.30 m/s.Find the wavelength of the wave in shallow water.
6cm
5Hz
Give three features of alkali metals that make them different from normal metal
Low density
Very soft
Low melting and boiling points
Extremely reactive