Sometimes true depending on your problem
Answer:
option D = N₂ + 3H₂ → 2NH₃
Explanation:
The reaction in which the nitrogen and hydrogen are reacted to form the ammonia is true.
N₂ + 3H₂ → 2NH₃
In this reaction we can see that one molecules of nitrogen react with three molecules of hydrogen and form two molecules of ammonia.
while the other options are in correct because,
2SO₂ + O₂ → 2SO₃
In this reaction two molecules of SO₂ react with one molecule of oxygen and form two molecules of SO₃.
2H₂S + 3O₂ → 2SO₂ + 2H₂O
In this reaction two molecules of H₂S react with three molecules of oxygen and produced four molecules of product.
SnO₂ + 2H₂ → Sn + 2H₂O
This is also incorrect because three molecules of reactant form three molecules of product.
Answer:Classify each of the following chemical reactions.
S + O2 → SO2
CaCl2 + 2AgNO3 → Ca(NO3)2 + 2AgCl
Zn + CuSO4 → Cu + ZnSO4
2Na2O → 4Na + O
Explanation:
synthesis and combustion
double replacement
single replacement
decomposition only
Answer:

Explanation:
We are asked to find how many kilojoules of energy would be required to heat a block of aluminum.
We will use the following formula to calculate heat energy.

The mass (m) of the aluminum block is 225 grams and the specific heat (c) is 0.897 Joules per gram degree Celsius. The change in temperature (ΔT) is the difference between the final temperature and the initial temperature.
- ΔT = final temperature - inital temperature
The aluminum block was heated from 23.0 °C to 73.5 °C.
- ΔT= 73.5 °C - 23.0 °C = 50.5 °C
Now we know all three variables and can substitute them into the formula.
- m= 225 g
- c= 0.897 J/g° C
- ΔT= 50.5 °C

Multiply the first two numbers. The units of grams cancel.



Multiply again. This time, the units of degrees Celsius cancel.


The answer asks for the energy in kilojoules, so we must convert our answer. Remember that 1 kilojoule contains 1000 joules.

Multiply by the answer we found in Joules.




The original values of mass, temperature, and specific heat all have 3 significant figures, so our answer must have the same. For the number we found, that is the tneths place. The 9 in the hundredth place tells us to round the 1 up to a 2.

Approximately <u>10.2 kilojoules</u> of energy would be required.
The electron is travelling with a velocity of 1.123 × 10⁷m/s if it has a wavelength of 8.20 km.
<h3>How to calculate velocity of an electron?</h3>
The velocity at which an electron travels can be calculated using the following formula:
λ = h/mv
Where;
- H = Planck's constant
- m = mass of electron
- v = velocity of electron
- λ = wavelength
- Planck's constant (h) = 6.626 × 10−³⁴ J⋅s.
- mass of electron (m) = 9.109 × 10−³¹ kg
- wavelength = 8200m
8200 = 6.626×10−³⁴ / 9.109 × 10−³¹V
8200 = 7.3 × 10-⁴V
V = 8200 ÷ 7.3 × 10-⁴
V = 1.123 × 10⁷m/s
Therefore, the electron is travelling with a velocity of 1.123 × 10⁷m/s if it has a wavelength of 8.20 km.
Learn more about velocity at: brainly.com/question/13171879
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