If the liquid is at or above its flash point, the flame spread rate is fast, and the entire pool is engulfed within seconds. ... As the liquid temperature decreases, flame radiation must both heat the liquid to the flash point temperature and supply the heat of vaporization.
Answer:
Explanation:
The model written correctly is:
This is a mathematical question, instead of a chemistry question, and you should use calculus to find the nitrogen level that gives the best yield, since this is an optimization problem.
The best yield is the maximum yield, and the maximum, provided that it exists, is found using the first derivative and making it equal to zero: Y' = 0
To find Y' you must use the quotient rule.
Now make Y' = 0
- The denominator is never equal to zero, because it is always positive and greater than 9.
- Make the numerator equal to zero:
9k - kN² = 0
- Since k is a positve constant, it is not equal to zero, and the other factor, 9 - N², must be equal to zero:
9 - N² = 0 ⇒ (3 - N) (3 + N) = 0
⇒ 3 - N = 0 or 3 + N = 0 ⇒ N = 3 or N = -3.
Since N is nitrogen level, it cannot be negative and the only valid answer is N = 3.
You can prove that it is a maximum (instead of a minimum) finding the second derivative or testing some points around 3 (e.g. 2.5 and 3.5).
Any substance changes to another substance that means the change of the physical property. Like water () has different state which changes as the temperature changes. It remain as liquid in the room temperature, in solid form at or below 0°C and vapor phase on or above 100°C. But in all the stage or phase of the substance the composition of the water i.e. remains. Thus the chemical property remains fixed when a substance change to other substance.
Answer:
that's because....
group 1 (e.g Na, K) those tend to lose one electron to gain noble gas electron configuration.
they can achieve that by just losing one electron from their outer shell.
as you go down the group 1, element gets bigger in size, which means there is more space between nucleus (which is in center of atom) and electron of outer shell. the more far away they are the less attraction force between them.
so its easier for potassuim to lose one electron than for lithuim.
so that means potassium will easily give up 1 electron to react with non metal or other element therefore it is more reactive than lithuim
but in case of non metal, the opposite happens but simple to understand.
as you go down the group 7 (halogen- Cl, Br, I) element will get bigger therefore force between nucleus and outer electron is getting smaller. they have to gain 1 electron in order to fill the outer shell (to gain noble gas electron configuration.)
as florine is more smaller in size than clorine it is more reactive because florine has more tendency to pull extra electron from metal or other element towards its side. so it easily gain 1 electron to react.
Answer:
Ca²⁺ + 2 OH⁻ → Ca(OH)₂(s)
Explanation:
In chemistry, the net ionic equation is a way to write a chemical reaction whereas you write only the ions that are involved in the reaction.
When calcium chloride, CaCl₂ reacts with sodium hydroxide, NaOH to produce Ca(OH)₂ the only ions involved in the reaction are Ca²⁺ and OH⁻, thus, the balanced net ionic equation is:
<em>Ca²⁺ + 2 OH⁻ → Ca(OH)₂(s)</em>
<em>Cl⁻ and Na⁺ are not involved in the reaction and you don't have to write them.</em>
