3*40+3*2*35.5=333* Avogadro’s number =
1.98*10^25
Answer:
C
Explanation:
The presence of mobile electrons explains the reason why there is conduction of electricity in the solid state. Electrons are the part of atoms that are majorly responsible for the different characteristics that substances exhibit.
A good example of the conduction of electricity can be seen in the case of 2 crystalline forms of carbon. While one of the allotropes could conduct electricity, the other allotrope cannot conduct electricity.
The two allotropes we are talking about here is graphite and diamond. While graphite could be used in a whole lot of electrolysis set up as an electrode, diamond does not found use in cases like this despite its crystalline structure. The reason for this is simple.
While diamond does not contain free mobile electron in its molecule, these free mobile electrons are present in a molecule of graphite. These free mobile electrons are the main reason why graphite can conduct electricity and diamond cannot even though they are both crystalline forms of carbon.
Atomic percentages<u>: 68% of copper and 32% of nickel.</u>
How this is calculated?
The given alloy is 100 g ,
m(Cu) = 0,7 · 100 g = 70 g.
m(Ni) = 0,3 · 100 g = 30 g.
n(Cu) = m(Cu) ÷ M(Cu) = 70 g ÷ 63,546 g/mol
n(Cu) = 1,10 mol.
n(Ni) = m(Ni) ÷ M(Ni) = 30 g ÷ 58,71 g/mol
n(Ni) = 0,51 mol
n(Cu) : n(Ni) = 1,10 mol : 0,51 mol
%(Cu) = 1,1 mol ÷ 1,61 mol = 0,68 = 68 %.
Similarly, %(Ni)=32%
What are Cu-Ni alloys?
- Cu-Ni alloys are alloys of copper (base metal with the largest individual content) and nickel with or without other elements, whereby the zinc content may not be more than 1%.
- When other elements are present, nickel has the largest individual content after copper, compared with each other element.
- As with other copper alloys, it is necessary to distinguish between wrought alloys, which are processed to semi-finished products, and cast alloys, from which castings are produced by various casting processes.
To know more about Cu-Ni alloys, refer:
brainly.com/question/16856761
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Answer:
40.02 calories
Explanation:
V = 10 mL = 10g
we know t went <em>up</em> by 4°C, this is our ∆t as it is a change.
Formula that ties it together: Q = mc∆t
where,
Q = energy absorbed by water
m = mass of water
c = specific heat of water (constant)
∆t = temperature change
Q = (10 g) x (4.186 J/g•°C) x (4°C)
Q = 167.44 J
Joules to Calories:
167.44 J x 1 cal/4.184 J = 40.02 calories
(makes sense as in image it is close to the value).
A. A piece of Iron being heated until it melts
Because it goes from solid to liquid.
A physical change is changing from solid to a liquid, a liquid to a gas, a gas to a liquid, a liquid to a solid, a solid to a gas, or a gas to a solid.
