Which of these is an example of a physical change?

a) burning a log

b) ripping a piece of paper

c) steel rusting

d) wood decaying

As temperature increases, density increases. True or False

Write the ion symbol for an atom with the given number of protons and electrons. a. 35 protons and 36 electrons

How are fossil fuels formed? A. Volcanoes erupt, bringing up energy from underground. B. Plants and animals decompose underground. C. Fossils combust and release petroleum D. The sun sends energy to Earth.

Base your answer to this question on the information below. During a bread-making process, glucose is converted to ethanol and carbon dioxide, causing the bread dough to rise.

On a 10-fold dilution of a strong acid, the ph will

Using special equipment which layer of the sun atmosphere is visible during a total solar eclipse

The characteristic flame test colors of metal ions are due to atomic emission spectra. Duscuss the relationship between the absoption and emission of light and the factors responsible for flame test colors.

Should a bartender use ice and scoop directly from ice machine or use an ice holding device and scoop to make drinks and refill drinks from

What classification should this reaction have? 4Al + 3O2 → 2Al2O3

If you start with 100 grams of a radionuclide, how much will you have after two half-lives have passed?