An atom of an element has 28 innermost electrons and 7 outermost electrons. In which period of the Periodic Table is this element located?

1. 5

2. 2

3. 3

4. 4

Cryolite, na3alf6 (s), an ore used in the production of aluminum, can be synthesized using aluminum oxide. start this question by first balance the chemical equation.

Question 2 unsaved a neutral atom has an atomic number of 20 and a mass number of 42. How many electrons does the atom have?

Sulfur and oxygen form both sulfur dioxide and sulfur trioxide. When samples of these are decomposed, the sulfur dioxide produces 3.49 g oxygen and 3.50 g sulfur, while the sulfur trioxide produces 6.75 g oxygen and 4.50 g sulfur.

Using the bohr model describe the changes in electrons energy and electron location when an atom changes from the ground state to an excited state.

Describe the relationship between the ohm and voltage?

What is the molarity of a solution that has 548 grams of HCl dissolved in 1.50 l water?

Steve puts some cheddar cheese in a pan on the stove and starts to melt it. After a little while, there is a layer of oil floating on top of the cheese. From the way the cheese melted, Steve knows it is a A Element B Solid C Mixture D Pure Substance.

Which experimental feature of the MALDI-MS technique allows the separation of ions formed after the adduction of tissue molecules? A) Distance travelled by ions depends on the ion charge. B) Velocity of ions depends on the ion mass-to-charge ratio.

Which temperature is required for the cell potential to be the standard cell potential? A) - 273°C B) 100°C C) 25°C D) 0°C

1. the purpose of the aqueous solutions in a galvanic cell is to? a. provide ions to be oxidized and reduced b. provide a path for the free flow of electrons c. maintain charge balance in the cell d. correct any volume changes in the cell 2.