sciences exam

  • Positive objects attract a negative object

  • A positive object repels a positive object

  • Negative and negative repel each other

  • Like charges repel and opposites charges attract

  • The danger of a short circuit is prevented by a fuse or breaker

  • In a series circuit consisting of a battery and 2 light bulbs. If one light bulb burns out the current (amount of electricity drops to 0 in the entire circuit)

  • In a series circuit, the current is the same at every point.

  • Oxygen is not a product of reparation (cellular)

  • Bioaccumulation - the process by which the concentration of a substance increase at it moves up in the food chain

  • The end of state of a very massive star is a black hole

  • The process by which the sun produces energy is called fusion

  • There are 8 atoms in CH3OOH

  • Isotopes have the same number of protons, but different neutrons

  • Sulfur has 6 valence electrons 

  • NaCl is an example of an ionic compound because it has a metal

  • Molecular bonds result from the sharing of electrons between atoms 

  • Neon is a noble gas

  • Elements in the same group have similar chemical properties

  • Ca,Sr, Ba, Ra of the same group.

  •  Fr is a metal

  •  # of valence electrons in Fr is 1 e

  •  Atomic mass-atomic number = 136 neutrons for Fr 

  •  Group 1(alkali metals)

  • A large beaker contains 30 ml of water, 350 ml of pb is added to the beaker causing the water volume to increase the 42ml (42-30=12 ) (D= m/v) (D=350/12) (D=29.2g/ml)

  • E= P x t (E=Energy [KJ] , P=Power, t=Time)

  •  For power - P=E/T 

  •  5w=18kj/h - UNITS OF WATTS (Multiply to the rest of the equation)

  •  (11p,12n) 2e) 8e) 1e) Na diagram

  • Halogens are highly reactive

  • Nebula is the birth of a star

  • Which trophic level would receive the most energy: Producers (we lose energy as we move up each trophic level)

  • Give an example of an organism in the trophic level: Plants 

  • Ex of omnivore: Bears, birds, humans

  • What is a coyote? Omnivore

  • The ozone layer protects us from harmful rays

  • V = voltage/potential difference (volts)

R = resistance (ohms 𝝮)

I = current (amps)

  • the current/voltage (v) is the same throughout

  • Short lines in a circuit diagram tells you the number of cells in a bjattery

  • Long lines

  • Electrons travel from the negative to positive, the electricity can take 2 paths

  • This is parallel circuit because there is more than one path

  • Resistance occur when the electrons slow down, a lot of resistance can cause overheating