The heat that is required to raise the temperature of an object is calculated through the equation,
heat = mass x specific heat x (T2 - T1)
Specific heat is therefore calculated through the equation below,
specific heat = heat / (mass x (T2 - T1))
Substituting,
specific heat = 645 J / ((28.4 g)(15.5 - - 11.6))
The value of specific heat from above equation is 0.838 J/g°C.
Answer:
B. PhCHO
Explanation:
Every organic group shows a characteristic IR absorption at certain wavelength . With the help of these absorption spectra we can identify the group present on organic molecules .
The wave number of 2710 cm⁻¹ is absorbed by aldehyde bond stretching .
The wave number of 1705 cm⁻¹ is shown by conjugated aldehyde . So the most likely compound among given compounds is PhCHO .
We calculate for the amount of chromium metal in the reactant by,
= 350 x (mass of Cr2/mass of Cr2O3)
= 350 x (104/152)
= 239.47 grams
The amount of Cr metal in the product is only 213.2 grams. Thus, the percent yield.
percent yield = (213.2 grams/239.47) x 100%
= 89%
Scott traveled 10 miles in his journey.
<u>Explanation</u>:
Scott first travels 5 miles in north direction, then he turns to west and covers 3 miles distance finally he turns to south and travels 2 miles. We need to find the total distance covered by the Scott. To find the distance we should sum up all the distances he covered in three directions 5 miles north + 3 miles west + 2 miles south = 10 miles.
Therefore we can conclude that the total distance traveled by the Scott is 10 miles.
Answer is: concentration of ammonium ions are 7,14·10⁻¹⁴ M.
Chemical reaction: 2NH₃(l) → NH₄⁺(am) + NH₂⁻(am).
Kam = 5,1·10⁻²⁷.
[NH₄⁺] · [NH₂⁻] = x; equilibrium concentration of cations and anions.
Kam = [NH₄⁺] · [NH₂⁻].
Kam = x².
x = [NH₄⁺] = √5,1·10⁻²⁷.
[NH₄⁺] = 7,14·10⁻¹⁴ M.