the most reactive element is Francium like xV1P3R said but it goes down group one and furthest left to find it.
As a general rule groups 1, 2 and 3 want to gain electrons to fill their shells, whereas groups 4, 5, 6 want to lose electrons to make themselves stable.
All of group 8's valence shells are full.
Waves
LIGHT WAVES
Wavelength - distance from one wave to another in the same place
Amplitude - height of wave from the medum
Trough - the bottom tip of a wave below the medium
Crest - the top of a wave above the medium
Frequency - is found by how how many waves appear (note: full wave includes both crest & trough)
SOUND WAVES
........ . . . . . . . . . .........
........ . . . . . . . . . . .........
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( Rarefraction ) Compression
To remember think RAREfraction RAREly any dots
COMPRESSION dots are COMPRESSED
Another thing to be aware of with waves is the doppler effect which just means high pitch to low pitch, like when a car going faster than you drives past it sound higher then it sounds lower.
ELECTRICITY
Another thing to remember with the relationship between voltage, current and resistance is that is is exactly like the distance over time x speed thing, it forms a pyramid. The voltage replaces distance; resistance, time; and current, speed.
btw GOOD LUCK WITH SCIENCE TOMORROW
i probs wont be doing to well - stupid mc skills
i'm so bad at them but know all the stuff