An atom of phosphorus has an atomic number of 15 and a mass number of 31. how many protons and neutrons does it contain?

What force of attraction does the second energy level of a phosphorus atom feel from the nucleus?

Which has the lighter mass one mole of platinum or one mole of zirconium?

What is the formula units for sodium sulfide, sodium sulfite, anf sodium sulfate?

2 Polnts What do the letters in the boxes of the periodic table represent? A. The letters stand for the names commonly used for the elements. O B. The letters are a one - or two-letter symbol assigned to each element. O C.

What goes along with the "drawing conclusions" step in the scientific method? A. Publish Results B. Test the Hypothesis C. Collect the Data D. Analyze the data

1 75 ml of lemon juice are added to 50 ml of water. What is the percent by vo of the solute?

How many moles of tungsten atoms are in 4.8 x 1025 atoms of tungsten?

At what speeds do you criuse down the track of a roller coaster

A sample of hydrogen gas is mixed with water vapor. The mixture has a total pressure of 755 torr and the water vapor has a partial pressure of 24 torr. What amount (in moles) of hydrogen gas is contained in 1.55 L of this mixture at 298 K?

Both equation I and II are balanced, but equation II is the correct way to write the balanced equation. Why do you think this is? (Hint: Think fractions.) I) 2 SnO2 + 4 H2 → 2 Sn + 4 H2O II) SnO2 + 2 H2 → Sn + 2 H2O