Answer:
Samarium
Explanation:
The element Sm describe is called Samarium. This element has unique sets of properties that makes it very unique and distinct.
The lanthanides are found in the f-block on the periodic table of elements.
This element is a moderately hard silvery metal that readily oxidizes in air. It assumes an oxidation state of +3. The element has an atomic number of 62
Answer:

Explanation:
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In this case, since the chemical reaction between copper and nitric acid is:

By starting with 0.80 g of copper metal (molar mass = 63.54 g/mol) and considering the 1:1 mole ratio between copper and copper (II) nitrate (molar mass = 187.56 g/mol) we can compute that mass via stoichiometry as shown below:

However, the real reaction between copper and nitric acid releases nitrogen oxide, yet it does not modify the calculations since the 1:1 mole ratio is still there:

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Answer:
Specific heat of metal = 0.26 j/g.°C
Explanation:
Given data:
Mass of sample = 80.0 g
Initial temperature = 55.5 °C
Final temperature = 81.75 °C
Amount of heat absorbed = 540 j
Specific heat of metal = ?
Solution:
Specific heat capacity:
It is the amount of heat required to raise the temperature of one gram of substance by one degree.
Formula:
Q = m.c. ΔT
Q = amount of heat absorbed or released
m = mass of given substance
c = specific heat capacity of substance
ΔT = change in temperature
ΔT = 81.75 °C - 55.5 °C
ΔT = 26.25 °C
540 j = 80 g × c × 26.25 °C
540 j = 2100 g.°C× c
540 j / 2100 g.°C = c
c = 0.26 j/g.°C
<span>The density of a material = mass/ volume
From the question, volume = 6 cm^3. Since the density = 8.9 g/cm^3
We have that 8.9 = mass/ 6
So mass = 8.9 * 6 = 53.4
So it follows that our mass = 53.4g. Hence option D which is 53g.</span>