Which element is in 3 period group 2

Conservation of mass

A molecule of a certain compound contains two nitrogen atoms and four oxygen atoms what is the molecular formula for this compound

A saline solution similar to that used for intravenous drips is made by dissolving 0.45 g sodium chloride in 50.00 g water. Which of the following statements concerning the saline solution and the law of conservation of mass is/are correct?1.

During the fission of uranium-235, neutrons are released and a small amount of mass is converted to energy. How many neutrons are in the nucleus of an atom of uranium-235? A. 92 B. 143 C. 235 D. 238

Which of the following statements regarding matter is false? All matter has mass. All life is composed of matter. All matter exists in the form of compounds. All matter is composed of elements.

If I have a 200 L container filled with nitrogen at a pressure of 1.0 atm, how many moles of nitrogen are present at 25 degrees C?

In the periodic table, a set of properties repeats from

Consider the model of the nitrogen atom. Which electron configuration matches this model? 1s22s22p2 1s22s22p3 1s22s22p4 1s22s22p5

In this experiment, you need to examine the idea of thermal energy transfer. Using a controlled experiment, .

What is the pressure of 2.3 moles of carbon dioxide gas stored in a 2 liter container at a temperature of 423 K? Given: a = 3.59 liters2 ∙ atmospheres/mole2, b = 0.0427 liters/mole, and R = 0.08205 liters∙atmospheres/K∙mole 37.22 atm 41.96 atm 79.