D is the answer your looking for
Answer:
Zero
Explanation:
Recall that;
E = q + w
Where;
q = heat, w = work done
When heat is absorbed by the system q is positive
When heat is evolved by the system q is negative
When the system does work, w is negative
When work is done on the system w is positive
Step 1
ΔE1= 60 KJ + 40 KJ = 100KJ
Step 2
ΔE2= (-30 KJ) + (-70 KJ) = (-100) KJ
ΔE1 + ΔE2= 100KJ + (-100) KJ = 0KJ
Answer:
The order of elements by volume-fraction (which is approximately molecular mole-fraction) in the atmosphere is nitrogen (78.1%), oxygen (20.9%), argon (0.96%), followed by (in uncertain order) carbon and hydrogen because water vapor and carbon dioxide, which represent most of these two elements in the air, are variable.
I copied and pasted but I hope this information is helpful :)
Answer:
Aluminum is ideal for aircraft manufacture because it's lightweight and strong. Aluminum is roughly a third the weight of steel, allowing an aircraft to carry more weight and or become more fuel efficient. Furthermore, aluminum's high resistance to corrosion ensures the safety of the aircraft and its passengers.
Explanation:
Answer:
a. 9.2
b. 4.4
c. 6.3
Explanation:
In order to calculate the pH of each solution, we will use the definition of pH.
pH = -log [H⁺]
(a) [H⁺] = 5.4 × 10⁻¹⁰ M
pH = -log [H⁺] = -log 5.4 × 10⁻¹⁰ = 9.2
Since pH > 7, the solution is basic.
(b) [H⁺] = 4.3 × 10⁻⁵ M
pH = -log [H⁺] = -log 4.3 × 10⁻⁵ = 4.4
Since pH < 7, the solution is acid.
(c) [H⁺] = 5.4 × 10⁻⁷ M
pH = -log [H⁺] = -log 5.4 × 10⁻⁷ = 6.3
Since pH < 7, the solution is acid.
