The element beryllium (Be, atomic number 4 and atomic mass 9) is right above magnesium (Mg, atomic number 12 and atomic mass 24) in the periodic table. How many more electrons does magnesium have than beryllium?

Why are both accuracy and precision important in making a measurement

A jar contains several different types of atoms. The proportions of these atoms can be changed slightly without changing any substance in the jar. This jar contains A. A molecule. B. A single element. C. A compound. D. A mixture.

What is Wesley Harris, the writer of this account, trying to escape

Calculate the mass ratio of zinc to iodine in zinc iodide. (mass of zinc consumed is 1.05g and mass of iodine consumed is 1.98g) Mass of ZnI2 after reaction is 2.45g?

How many total moles of ions are released when the following sample dissolves completely in water? 7.1 mol of NH4Cl

A 150ml sample of hydrochloric acid completely reacted with 60.0mL of a 0.100 M NaOH solution. What was the original concentration of the HCl solution

Rearrange in to a quadratic 5.333 = (0.6 + 2p) ² / (0.135 - p)

How hot would a 2.3 L balloon have to get to expand to a volume of 3.0 L? Assume the initial temperature of the balloon is 24 °C, and that the pressure inside the balloon remains constant. A. 3 K B. 42 K C. 128 K D. 390 K

Which pair of nitrogen bases will form a bond in a DNA molecule? a. cytosine and adenine b. adenine and thymine c. guanine and thymine d. thymine and cytosine

Most meteors that fall into the earths atmosphere burn up before reaching the ground. Why is this?