A chemical change occurs when

a. dissolved minerals solidify to form a crystal.

b. ethanol is purified through distillation.

c. salt deposits form from evaporated seawater.

d. a leaf changes color in the fall.

The electron configurations of two unknown elements X and Y are shown. X: 1s^ 2 2s^ 2 2p^ 6 3s^ 1 Y: 1s^ 2 2s^ 1 Which statement is most likely correct about the two elements?

A 1.8-mL volume of seawater contains about 4.0 * 10^-10 g of gold. The total volume of ocean water is about 1.5 * 10^21 L. Calculate the total worth of all the gold in the world's oceans if the price of gold is $19.

Calculate the formula mass of ethanol, c2h5oh. express your answer to three significant figures and include the appropriate units.

The following characteristics describe which of these terms? The substance is not uniform in appearance and each part of the mixture contains a combination of different ingredients in different ratios.

Consider the molecule so3. part a what is the electron configuration of an isolated s atom?

How many grams of zinc metal will react completely with 8.2 liters of 3.5 M HCl? Show all of the work needed to solve this problem. Zn (s) + 2 HCl (aq) ZnCl2 (aq) + H2 (g)

The notation for the nuclide 13755Cs gives information about (1) mass number, only (2) atomic number. only (3) both mass number and atomic number (4) neither mass number nor atomic number

Which is an example of pure chemistry

When making broccoli cream soup, the broccoli and aromatics should be A. sweated. B. puréed. C. simmered. D. burned.

Plants absorb light energy and store that energy in the form of what? A water B carbon dioxide C sugar D oxygen