During the Paleocene-Eocene Thermal Maximum (PETM) 55.8 million years ago a significant amount of carbon was released into the ocean and atmosphere in a relatively short amount of time (less than 10,000 years). Based on the evidence from fossilized plant leaves in Bighorn Basin in Wyoming, which of the following happened in that region during the PETM? Select all that apply.

Which of the following pairs of elements belong to the same groupa. h and he b. li and bec. c and pb d. ga and ge

Consider three unlabeled bottles, each contain small pieces of one of the following metals. - magnesium - sodium - silver the following reagents are used for identifying the metals. - pure water - a solution of 1.0 molar hcl - a solution of concentrated hno3 (a) which metal can be easily identified because it is much softer than the other two? describe a chemical test that distinguishes this metal from the other two, using only one of the reagents above. write a balanced chemical equation for the reaction that occurs. (b) one of the other two metals reacts readily with the hcl solution. identify the metal and write the balanced chemical equation for the reaction that occurs when this metal is added to the hcl solution. use the table of standard reduction potentials (attached) to account for the fact that this metal reacts with hcl while the other does not. (c) the one remaining metal reacts with the concentrated hno3 solution. write a balanced chemical equation for the reaction that occurs. (d) the solution obtained in (c) is diluted and a few drops of 1 m hcl is added. describe what would be observed. write a balanced chemical equation for the reaction that occurs.

Compare and contrast the bohr model and the electron cloud models of the atom.