Answer:
The current temperature is -15° (15° below zero)
Explanation:
The temperature drops 10°:
T-10°
It will reach 25° below zero:
T - 10° = -25°
We add 10° in both members of the equation:
T - 10° +10° = -25° +10°
The equation is simplified as follows:
T = -25° +10°
T = -15°
The integer -15° can be expressed as 15° below zero.
Answer:
27%
Explanation:
Hello,
The following information is missing, but I found it: "1.92 g of sodium sulfate is produced from the reaction of 4.9 g of sulfuric acid and 7.8 g of sodium hydroxide" so the undergoing chemical reaction is:
Now, to compute the percent yield, we must first establish the limiting reagent to subsequently determine the theoretical yield of sodium sulfate because the real (1.92g) is already given, thus, we consider the following procedure:
- The moles of sodium hydroxide that completely react with 0.05 moles of sulfuric acid are:
As this number is higher than the previously computed 0.05 moles of available sulfuric acid, one states that the sulfuric acid is the limiting reagent. Now, the theoretical grams of sodium sulfate are found via:
Finally, the percent yield turns out into:
%
Best regards.
Lets take a moment to list all the characteristics of the group 18 (also known as noble gases and/or group 8) elements:
- They have 8 valence electrons.
- Don't need ANY more electrons because their octet is full (stable).
- Are stable
- Not reactive
- Known as the noble gases
Now.. lets take some time to think about why elements want to form ions:
Elements form ions to either gain or lose valence electrons to the element they bond with. This helps them GAIN a full octet. What is a full octet, you may ask? An octet is when an element has all 8 valence electrons and is stable, making it nonreactive.
Why would an element with a full octet want to bond? It already has a full octet, it does not need to bond.
That, my fellow Brainly user, is why the noble gases do not need to bond.
I really do hope this helps! Enjoy, and good luck on the studies.
The reaction must be a + b --> c
Then you can predict a reaction rate, r o the type r = k * a^n * b^m
Given that the reaction rate is not affected by the concentration of b you can state that m = 0 and r = k * a^n.
Now given, that there is a proportional relation between the reaction rate and a (double a gives double rate), then n = 1 and r = k*a. You can verify that if you dobule a r also doubles.
Answer: r = k*a
