I hope this helps in some way. I forgot to mention that the question states they want to find THE NUMBER OF MOLES for H2O. Yherefore, you would want mol of H2O on top.
<u>Answer:</u>
The correct answer option is 1.6 atm.
<u>Explanation:</u>
We know that there is a sample gas which has a volume of 2.4 L with a pressure 1.2 atm and we are to find the pressure of the same gas sample if its volume is reduced to 1.8 L at a constant temperature.
We will apply the Boyle's law here which states that the "pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature".
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Substituting the values in the formula to get:
Therefore, the pressure of the same gas sample will be 1.6 atm if the volume is reduced to 1.8 L at a constant temperature.
Answer:
a) Na
c) Na
b) Sr
d) Ca
Explanation:
As we move from left to right across the periodic table the number of valance electrons in an atom increase. The atomic size tend to decrease in same period of periodic table because the electrons are added with in the same shell. When the electron are added, at the same time protons are also added in the nucleus. The positive charge is going to increase and this charge is greater in effect than the charge of electrons. This effect lead to the greater nuclear attraction. The electrons are pull towards the nucleus and valance shell get closer to the nucleus. As a result of this greater nuclear attraction atomic radius decreases and ionization energy increases because it is very difficult to remove the electron from atom and more energy is required.
As we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
As the size of atom increases the ionization energy from top to bottom also decreases because it becomes easier to remove the electron because of less nuclear attraction and as more electrons are added the outer electrons becomes more shielded and away from nucleus.
Atomic mass (K)= 39.1 amu
therefore:
1 mol (k)---------------------39.1 g
x------------------------------- 2.25 g
x=(1 mol * 2.25 g) / 39.1 g=0.05754....≈0.06 moles
Answer: 0.06 moles.
