Is spoiling food a physical or chemical change

Some common substances used in the laboratory are listed in the table. the chemical formulas of the substances are also listed beside their names. q: a. how many of the listed items are elements? a. 3 b. 4 c. 5 d. 6

What trend does the atomic radius follow along a period on the periodic table? A. The atomic radius gets smaller the farther right it appears on the periodic table. B. The atomic radius gets larger the farther right it appears on the periodic table.

What's 13 in scientific notation

Consider the following reaction: N2 (g) + 3H2 (g) 2NH3 (g) Determine the standard free energy of the the reaction at298K?

Which of these methods could be used to separate an insoluble solid from a soluble solid? Melting the mixture and then using a filter to separate out the soluble solid Melting the mixture, mixing it with water, and then using a magnet to separate

What mass of oxygen gas is produced by the reaction of 3.8 g of ammonium perchlorate?

In the space provided write an electron configuration for a silicon atom in the excited state

Coenzyme q carries electrons between which stages of the electron-transport chain?

Concerning the 10.0 mL of 0.50 M NaCl to 100 mL of solution: When a solution is diluted, does it change the number of moles dissolved?

How is the structure of atoms altered during fission and fusion?