I mole of water has an Avogadro number of molecules.
1 mole = 6.02 * 10^ 23 molecules.
6.02 * 10^ 23 molecules = 1 mole of water
1 molecule = 1/(6.02 * 10^23) mole of water
2.0 * 10^22 molecules would have = (2*10^22) * 1/(6.02*10^23)
= 0.033
2* 10 ^22 molecules of water would have 0.033 moles of water.
Answer:
1.18 moles of gas
Explanation:
3.00 moles of gas are pumped into a 1.00L rigid container with a pressure of 1.98 atm. The gas is released from the container until the pressure is 0.78 atm, how many moles of gas remain in the container?
for the sealed rigid container, the pressure is directly proportional to the amount of gas
3.00moles/1.98 atm = ? moles/0.78 atm
? = 3.00 X 0.78/1.98 =1.18 moles of gas
Answer:
B
Explanation:
We are talking about the periodic table in which elements where put under different rows and columns according to their atomic number (number of protons) in ascendant order.
In rows or periods we can find trends in some properties like atomic radius, electronegativity, etc...). So they are not similar in size. Option A is a false statement.
Also, they were organized in groups or columns according to their similar electronic configuration and chemical properties (like noble gases, halogens, etc...) This means option B is the correct statement.
M/V=D
40.5/15=2.7
The density of the block of aluminum is 2.7 g/cm³.
Answer: According to Moseley, similar properties recur periodically when elements are arranged according to increasing atomic number. Atomic numbers, NOT weights, determine the factor of chemical properties.
Mendeleev realized that the physical and chemical properties of elements were related to their atomic mass in a "periodic" way, and arranged them so that groups of elements with similar properties fell into vertical columns in his table
