Answer:
The correct option is;
True
Explanation:
Combustion is a chemical reaction between components of a combustion reaction which are;
1) A fuel
2) An oxidizing agent
The oxidizing agent or oxidant in a combustion reaction consist mainly of oxygen.
A combustion reaction is an oxidation and reduction (redox) heat evolving (exothermic) reaction that takes place at high temperatures and produces smoke which consists of gaseous mixture of chemicals and sometimes very small solid particles
An exothermic reaction can be classed either as rapid, spontaneous, or explosive
A spontaneous exothermic reaction is one that begins on its own in atmospheric conditions and room temperature as the heat required to begin the reaction is produced by the initial oxidation of the reacting fuel
Example of a substance that undergoes spontaneous oxidation reaction is white phosphorus.
Answer:- 71.7 calories
Solution:- it is a unit conversion problem where we need to convert joules into calories.
The unit conversion for these energy units is:
1 calorie = 4.184 joule
The given energy is 300 joules and has to be converted to calories. We will show the set up using dimensional analysis.
= 71.7 calories
So, the energy in calories is 71.7.
Answer:
A scientific claim is a statement about the results of your experiment that is supported by evidence gathered during the experiment and reasoning that explains how the evidence is connected to the claim. For example: Claim: Air is matter.
Explanation:
The mass in grams of butane at standard room temperature is 53.21 grams.
<h3>How can we determine the mass of an organic substance at room temperature?</h3>
The gram of an organic substance at room temperature can be determined by using the ideal gas equation which can be expressed as:
PV = nRT
- Pressure = 1.00 atm
- Volume = 22.4 L
- Rate = 0.0821 atm*L/mol*K
- Temperature = 25° C = 298 k
1 × 22.4 L = n × (0.0821 atm*L/mol*K× 298 K)
n = 22.4/24.4658 moles
n = 0.91556 moles
Recall that:
- number of moles = mass(in grams)/molar mass
mass of butane = 0.91556 moles × 58.12 g/mole
mass of butane = 53.21 grams
Learn more about calculating the mass of an organic substance here:
brainly.com/question/14686462
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Answer:
The first 50 elements along with their valences are given below :
1. Hydrogen = 1
2. Helium = 0
3. Lithium = 1
4. Beryllium = 2
5. Boron = 3
6. Carbon = 4
7. Nitrogen = 3
8. Oxygen = 2
9. Fluorine = 1
10. Neon = 0
11. Sodium = 1
12. Magnesium = 2
13. Aluminium = 3
14. Silicon = 4
15. Phosphorus = 3
16. Sulphur = 2
17. Chlorine = 1
18. Argon = 0
19. Potassium = 1
20. Calcium = 2
21. Scandiun = 3
22. Titanium = 3
23. Vanadium = 4
24. Chromium = 3
25. Manganese = 4
26. Iron = 2
27. Cobalt = 2
28. Nickel = 2
29. Copper = 2
30. Zinc = 2
31. Gallium = 3
32. Germanium = 4
33. Arsenic = 3
34. Selenium = 2
35. Bromine = 1
36. Krypton = 0
37. Rubidium = 1
38. Strontium = 2
39. Yttrium = 3
40. Zirconium = 4
41. Niobium = 3
42. Molybdenum = 3
43. Technetium = 7
44. Ruthenium = 4
45. Rhodium = 3
46. Palladium = 4
47. Sliver = 1
48. Cadmium = 2
49. Indium = 3
50. Tin = 4
<u>Note</u> :
An element like Iron, copper can have more than one valencies.
