Has an asteroid hit Earth in the past

What term is applied to a scientist who studies ancient life, including animal and plant fossils A. Anthropologist B. dendroclimatologist C. geophysicist D. Paleontologist

Within a family: the atomic radius will increase as you go down. Why?

Carbon-14 emits beta radiation and decays with a half-life (t) of 5730 years. Assume that you start with a mass of 6000 g of carbon 14. How many grams of the isotope remains at the end of four half-lives?

Which of the following statements is not true of the combustion of an organic compound? A. oxygen gas (O2) must be one of the reactants B. energy is released by the reaction C. it can also be described as a synthesis reaction D.

A single covalent bond involves two atoms sharing one pair of electrons. True False

What is true about the energy involved in a chemical reaction? A. The amount of energy is constant, but it is converted from one form to another. B. The amount of energy decreases as it is converted from one form to another. C.

Which state of matter is highly compressible, is made of particles moving independently of each other, and is present in large quantities near Earth's surface?

The air in an inflated balloon (the system) absorbs 125 J of heat from its proximity to a fire. The balloon expands and does 85 kJ of work. What is the change in internal energy (in kJ) (ΔU) for the system? Round to the nearest whole number.

Is a cytoplasm made of 80 percent of water

Calculate the acid concentration of a sample of acid rain with a ph of 4.20