A catastrophic disturbance that resulted in mass extinction marks the boundary of which two eras?

A. Precambrian time and Paleozoic era

B. Paleozoic era and Cenozoic era

C. Mesozoic era and Cenozoic era

D. None of the above

What is formation of methane

Which has the most thermal energy? A cup of water at 10°C or a lake at 10°C

How to tell how reactive an element is on the periodic table?

A sample of carbon dioxide occupies 2.77 L at a pressure of 18.1 psi and a temperature of 56ºC. What pressure will the carbon dioxide exert if the volume is increased to 4.81 L while the temperature is held constant?

An element has three naturally occurring isotopes. The relative abundances of the isotopes are 0.27%, 9.25%, and 90.48%. The most abundant isotope has an atomic mass of 19.99 amu. The least abundant isotope has an atomic mass of 20.

Why do some elements react easily but others dont?

1. What is an isomer? How many possible isomers of hexane are there? What are the structural differences between these isomers?

An ion of oxygen contains eight protons and has a charge of 2-. What must occur for this ion to become a neutral oxygen atom? Group of answer choices It must lose two electrons. It must gain two protons. It must gain two electrons.

If 46.1 g of copper at 11.6 °C is placed in 85.0 g of water at 72.4 °C, what is the final temperature of the mixture? The specific heat capacities of copper and water are 0.385 J/g. K and 4.184 J/g. K, respectively, a. 71.2 °C b. 51.0 °C C 69.5 °C d.

how many grams of water are produced when 15 grams of magnesium hydroxide are reacted with sulfuric acid