Answer:
oil floats on water because it is heavier than water
Salt is no longer visible after stirring as salt dissolves in water
by filtration
Answer: The resultant pressure is 3.22 atm
Explanation:
Gay-Lussac's Law: This law states that pressure is directly proportional to the temperature of the gas at constant volume and number of moles.
(At constant volume and number of moles)
where,
= initial pressure of gas = 2.79 atm
= final pressure of gas = ?
= initial temperature of gas = 273K
= final temperature of gas = 315 K

Thus the resultant pressure is 3.22 atm
Answer:
The answer is: D
Explanation:
A. They have the same number of electron energy shells. Is false, all the elements are in different periods so, they have different number of lectron energy shells.
B. They are all Halogens. No, is wrong, halogens are F, Cl ,Br
C. They have the same number of electrons. is wrong, if they had the same number of electrons they must be they same element and they aren't the same.
D. They are all Noble gases. Yes, it's true they are noble gases, they are the first group in the periodic table from the right.
Answer:
The same number of each element present before the reaction takes place must also be present on the product side of the equation. Coefficients are placed in front of a chemical formula to show the number of moles of that substances that are necessary for the reaction to occur.
Explanation: