Scientists have hypothesized that oxygen began to build up in the Earth's atmosphere after the development of living things with the ability to

a. breathe air.

b. form tissues.

c. photosynthesize.

d. reproduce sexually.

2NaHCO3-->Na2CO3+H2O+CO2

Any object that orbits around a larger object is called what

What is the limiting reactant if 4.0 g of Nh3 react with 8.0 g of oxygen?

What's the difference between natural gas, coal, and biomass?

Be sure to answer all parts. Consider the following balanced thermochemical equation for the decomposition of the mineral magne MgCO3 (s) → MgO (s) + CO2 (g) ΔHrxn = 117.

Complete the following statements about the functions of the digestive system. The starts an involuntary swallowing action when it senses food. The squeezes food down the digestive tract by an involuntary synchronized muscle movement called.

Explain how thermal energy is transferred through convection.

What are the coefficients that will balance this skeleton equation? a l c l 3 + naoh → al (oh) 3 + nacl?

Which cluster in the agriculture industry would be most likely to partner with the animal systems cluster to introduce new modern procedures to animal careers

Sarah is ordering cheese pizza for a party of ten people she knows each pizza has 8 slices to figure out how many pizzas to order sarah needs to know the