Respiratory system
The organ where gas exchange happens
Lung -> alveoli
"Reactants → Products" is called this
Word equation
Air is an example of mixture or pure substance
mixture
Force acting on a surface. Formula
Pressure
N/m2
What is alloy?
mixture of metal with other element
Muscle that helps breathing
What is the diaphragm?
Magnesium + oxygen → ?
magnesium oxide
Can be separated physically
mixtures
What is speed? how do we find it?
How fast object moves in a given time
Distance ÷ Time
What affects on size of moments?
distance from pivot or size of force
Gases we breathed in and out
oxygen and carbon dioxide
A reaction where a metal replaces another
displacement reaction
What is concentration?
Amount of solute in a solution
Object balances when…
clockwise = anticlockwise moments
Steeper line on distance/time graph means…
higher speed
Another system that works with respiratory system closely
Circulatory system
Carbon burns in good supply of oxygen to form carbon dioxide. What is word equation?
Carbon + Oxygen -> Carbon dioxide
Example of pure compound
Water
A force of 10 N is applied 0.5 m from the pivot. Calculate the moment about the pivot.
5 N·m
copper + silver nitrate -> copper nitrate + silver
why did it happened?
hint: silver less reactive
copper displaced silver in reaction
which organs move when be inhale and exhale and how
diaphragm and ribcage
inhale: ribcage rises and diaphragm flattens
exhale: ribcage falls and diaphragm rises
silver nitrate + sodium chloride -> silver chloride + sodium nitrate. Which ones are products and which one are reactants
silver nitrate + sodium chloride are reactants
silver chloride + sodium nitrate are products
How to make solution:
1)more concentrated?
2) less concentrated?
1) more solute
2) more solvent
Which applies more pressure? A: A 60N box with an area of 10m2 B: A 100N box with an area of 20m2
A has a pressure of 6Pascal and B has a pressure of 5pascal, so A applies more pressure.
What are exothermic and endothermic reactions
Exothermic reaction: releases heat → gets hot (combustion, respiration).
Endothermic reaction: absorbs heat → gets cold (photosynthesis, melting ice).