8.98
×
N
A
cobalt atoms
Explanation:
N
A
,
Avogadro's number
specifies
6.0221
×
10
23
individual particles. It is simply another collective number like a dozen, or a score, or a gross.
N
A
has the property that
6.0221
×
10
23
individual cobalt atoms has a mass of
58.93
⋅
g
. How did I know that? Did I have it memorized?
So the quantity is
≈
54
×
10
23
cobalt atoms.
I was hoping that some choices would be given to choose from. As there are no choices given, so i am answering the question based on my knowledge and hope that it comes to your help. Calcium hydroxide is a good example of Arrhenius base. An Arrhenius base is actually a substance that releases a hydroxyl ion in water.
Light basically evaporates pigments such as colored paper. Exposed pigment fading is kind of like getting colored paper wet. It will fade and bleed.
Your answer is B, conservation of mass
Recall that percent yield is given by: %Yeild = actual yeild/theoretical yeild x100
During experiments, there are errors made:
• uncertainty in measurements
• losses of reactants and products
• impurity in reactants
• losses during separation (e.g. filtration or purification)
• Some side reactions might also happen.
Among the given options, only conservation of mass does not contribute to a lower actual yield compared to the theoretical yield.
Answer:
a motor that requires no energy input once it is running
