How does the periodic table arrange the elements?

A. in alphabetical order

B. by chemical properties

C. by the date they were discovered

D. by how common they are on Earth

When a gas is cooled at constant pressure, what happens to its molecules and volume?

Describe how electron movement is related to the bonding in methane, CH4. A) Electrostatic sharing of electrons allows ionic bonds to form. B) The atomic orbitals overlap and share electrons to form covalent bonds.

Which planets atmosphere is composed primarily of nitrogen? A) uranus B) earth C) neptune D) saturn

Andreas wrote the following hypothesis: "If the number of livestock on Earth increases, then the amount of methane gas in the atmosphere will increase because cows produce methane gas as a by-product of digestion.

What is the advantage of having folded membrane surronding the cell or within the cytoplasm or within organelles

Of the following reactions, which one produces oxygen gas? Fermentation Anaerobic respiration Aerobic respiration Photosynthesis

Describe the electrodes in this iron-copper galvanic cell.

What happens to wood when it burns?

El cuerpo humano tiene unos 6 billones de células (6,0x1012) y la población de la Tierra es de unos 8 000 millones de personas. Con estos datos aproximados, calcula las moles de células humanas que hay en la Tierra.

True or false: an apple looks red because it absorbs red light?