Answer:
1. 0.0500 moles K, 0.0250 moles Cr and 0.1000 moles O.
2. 9.00 moles ammonium ions are present.
Explanation:
1. In 1mol of K2CrO4 there are 2 moles of K, 1 mole of Cr and 4 moles of O.
The moles in 0.0250 moles K2CrO4 are:
0.0250mol * 2 = 0.0500 moles K
0.0250mol * 1 = 0.0250 moles Cr
0.0250mol * 4 = 0.1000 moles O
2. In 1 mole of (NH4)2CO3 there are 2 moles of ammonium ions, NH₄⁺.
In 4,50 moles are:
4.50 moles * 2 = 9.00 moles ammonium ions are present
D. In a Chemical reaction, elements are not changed, just rearranged. Small amounts of energy take place.
Divide velocity by the wavelength.
The following answers:
1. B
2. D
