Steve, Sarah, Richard, and Kate each run paper chromatography on unknown liquids. Steve gets
a red band, Sarah gets a yellow band and a red band, Richard gets a green band and a red band,
and Kate gets a yellow band and a blue band.
Which student might have had a pure substance?
Sarah
Richard
Kate
Steve

Abullet found at a crime scene may be used as evidence in a trial if the percentage of metals match to the composition of metals in a bullet from the suspect's ammunition. a forensic scientist's analysis of the bullet shows that it contains 11.9 g of lead, 0.5 g of tin, and 0.8 b of antimony. what is the percentage of lead metal in the bullet? express your answers to the one's place.

If 10.0 ml of the solution on the right are withdrawn from the 100 ml beaker and diluted again in a similar manner, what is the new concentration? m nacl

If a 12-v battery is connected to a circuit that has a current of 3.0 a, what is the total resistance in the circuit? 36 ohms 4 ohms 0.25 ohms