calculate the amount of heat absorbed or released when 3.0 x 10 ^23 Iron atoms react with 1500. mL of oxygen gas at STP

Which traits do human embryos have that link them to a common ancestor with fish and reptiles? a. scales and tail b. gill slits and scales c. tail and gill slits d. hair and tail

A100-watt light bulb radiates energy at a rate of 100 j/s. (the watt, a unit of power or energy over time, is defined as 1 j/s.) if all of the light emitted has a wavelength of 525 nm , how many photons are emitted per second?

How does a scientist the government? a. the scientist tells people in society what to do. b. the scientist determines the policies that the government spends money on. c. the scientist provides unbiased information to the government. d. the scientist makes laws based on his or her research results.