Answer:
The volume of the solution is 0.305 liters.
Explanation:
Molar mass is the amount of mass that a substance contains in one mole. The molar mass of K₂Cr₂O₇ is 294 g / mole. Then you can apply the following rule of three: if by definition of molar mass 294 grams of the compound are contained in 1 mole, 180 grams are contained in how many moles?
moles= 0.61
Molarity is a measure of the concentration of a substance that is defined as the number of moles contained in a certain volume. So, the molarity of a solution is calculated by dividing the moles of the solute by the volume of the solution:
Molarity is expressed in units 
.
In this case:
- molarity= 2 M
- number of moles of solute= 0.61 moles
- volume= ?
Replacing in the definition of molarity:
Solving:
volume= 0.305 liters
<u><em>The volume of the solution is 0.305 liters.</em></u>
Answer:
1 mole of aluminum must contain 6.022⋅1023 atoms of aluminium → this is known as Avogadro's constant.
Explanation:
Answer:
The elements become less reactive.
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 and reactivity increases because of greater electron affinity.
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. The electron affinity decreases because of shielding effect and thus atom become less reactive.
Answer:
30 moles
Explanation:
Water is H2O, meaning there is 2 Hydrogen atoms and 1 Oxygen atom. Oxygen is O2, because it is a diatomic molecule. (Hydrogen is also a diatomic molecule, so H2)
The equation, balanced, would have to be: 2H2 + O2 -----> 2H2O
I multiply 15 moles O2 by the molar ratio of (hydrogen/oxygen)
15 mol. O2 * (2 mol. H2/1 mol O2) = 30 moles of water
