Answer:
ΔH = 125.94kJ
Explanation:
It is possible to make algebraic sum of reactions to obtain ΔH of reactions (Hess's law). In the problem:
1. 2W(s) + 3O2(g) → 2WO3(s) ΔH = -1685.4 kJ
2. 2H2(g) + O2(g) → 2H2O(g) ΔH = -477.84 kJ
-1/2 (1):
WO3(s) → W(s) + 3/2O2(g) ΔH = 842.7kJ
3/2 (2):
3H2(g) + 3/2O2(g) → 3H2O(g) ΔH = -716.76kJ
The sum of last both reactions:
WO3(s) + 3H2(g) → W(s) + 3H2O(g)
ΔH = 842.7kJ -716.76kJ
<h3>ΔH = 125.94kJ </h3>
Answer:
Nichrome
Answer: Hot water system coils are commonly made up of metal alloys which are a combination of two or more elements. The most commonly used metal alloy is “Nichrome”. Nichrome is an alloy of nickel (80%) and chromium (20%).
Answer:
your brain processes ever detail in a picture rather than words for for example a picture of something words doesn't describe it as well as the picture could.
Answer:
[H⁺] = 3.98×10⁻⁷ M
Explanation:
Given data:
pH of blood = 6.40
Hydrogen ion concentration = ?
Solution:
Formula:
pH = - log[H⁺]
by rearranging this formula,
[H⁺] = 10⁻(pH)
By putting values,
[H⁺] = 10 ⁻⁶°⁴⁰
[H⁺] = 3.98×10⁻⁷ M
The melting point of a particular compound is fixed and it is an important identification of an unknown compound. The practice to determine the melting point of an unknown material In different ratio with a known material is important to get the exact melting point of the unknown material. In different ratio the melting point of the unknown material will be fixed as the melting point of a pure material doesn't depend on the ratio in which they are mixed with other material. To get the exact melting point it is always good to get the melting point twice in different ratio.
