Answer is: there are 3.011·10²³ atoms of calcium.
n(Ca) = 0.50 mol; amount of substance(calcium).
Na = 6.022·10²³ 1/mol; Avogadro's constant or number.
N(Ca) = n(Ca) · Na.
N(Ca) = 0.50 mol · 6.022·10²³ 1/mol.
N(Ca) = 3.011·10²³; number of calcium atoms.
The mole is an SI unit which measures the number of particles in substance. One mole is equal to <span><span>6.022</span></span>·<span><span><span>10</span></span></span>²³<span> atoms.</span>
8 moles of water on the right side.
An oxidation-reduction or redox reaction is a reaction that involves the transfer of electrons between chemical items (the atoms, ions, or molecules involved in the reaction).
Redox reactions: the burning of fuels, the corrosion of metals, and even the processes of photosynthesis and cellular respiration involve oxidation and reduction.
Step 1:
MnO4- ----> Mn2+
2Cl- ------> Cl2
Step 2:
MnO4- --> Mn2+ + 4H2O
2Cl- -----> Cl2
Step 3:
8H+ + MnO4- ------> Mn2+ + 4H2O
2Cl- ----->Cl2
Step 4:
8H+ + MnO4- +5e- ------>Mn2+ + 4H2O
2Cl- ----> Cl2+ 2e-
Step 5:
16 H+ +2 MnO4- +10Cl- ----->2 Mn2+ + 8H2O+5Cl2
This is the balanced equation in an acidic medium.
That is 8, right side.
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True, Energy cannot be created or destroyed therefore it remains constant