During the period from about 1800 to about 1865, the atomic weights of many elements were accurately measured. Why was this important to Mendeleev's formulation of the periodic table?

How many moles of potassium are represented by 7.85 _ 1024 potassium atoms?

In a group 1 analysis, a student obtained a precipitate containing both AgCl and PbCh. Which of the following reagents would enable separation of AgCl (s) from PbCl (s) ? O Hys 0 Na2CO3 o KOH O NH3 O

In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. Which postulate of kinetic molecular theory best explains how this is possible? A.

At STP fluorine is a gas and iodine is a solid. This observation can be explained by the fact that fluorine has

The number of grams of water vapor in a cubic meter of air is called the

Combustion analysis of toluene, a common organic solvent, gives 8.20 mg of co2 and 1.92 mg of h2o. if the compound contains only carbon and hydrogen, what is its empirical formula?

Why does the moon have phases? What are the four main phases of the moon? How long does it take to change from one to another?

How many atoms are in 1/2 mole of calcium

Which of the following units is best when measuring the mass of an object?

When balancing an equation, should you adjust the subscripts or the coefficients?