Answer:
1.58x10⁻⁵
2.51x10⁻⁸
0.0126
63.10
Explanation:
Phenolphthalein acts like a weak acid, so in aqueous solution, it has an acid form HIn, and the conjugate base In-, and the pH of it can be calculated by the Handerson-Halsebach equation:
pH = pKa + log[In-]/[HIn]
pKa = -logKa, and Ka is the equilibrium constant of the dissociation of the acid. [X] is the concentrantion of X. Thus,
i) pH = 4.9
4.9 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = - 4.8
[In-]/[HIn] = 
[In-]/[HIn] = 1.58x10⁻⁵
ii) pH = 2.1
2.1 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -7.6
[In-]/[HIn] = 
[In-]/[HIn] = 2.51x10⁻⁸
iii) pH = 7.8
7.8 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = -1.9
[In-]/[HIn] = 
[In-]/[HIn] = 0.0126
iv) pH = 11.5
11.5 = 9.7 + log[In-]/[HIn]
log[In-]/[HIn] = 1.8
[In-]/[HIn] = 
[In-]/[HIn] = 63.10
Answer:
NH3
Explanation:
2NH3(aq)+CO2(aq)→CH4N2O(aq)+H2O(l)
So for two moles of NH3 we need one mole of CO2. So let's count moles for each reagent.
n(NH3)=m(NH3)/M(NH3)=135700/17,03=7968.29 mol
n(CO2)=m(CO2)/M(CO2)=211400/44.01=4803.45 mol
From equation we have to divide n(NH3) by 2 because we need two equivalent per one CO2. That will be 3984.145. So the limiting agent is NH3 because it's not enough of it to react with all CO2
Explanation:
For the given reaction:
Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.
![Rate=k[CO]^x[H_2]^y](https://tex.z-dn.net/?f=Rate%3Dk%5BCO%5D%5Ex%5BH_2%5D%5Ey)
where x and y are order wrt to 
and 
According to collision theory , the molecules must collide for a reaction to take place. According to collision theory , the rate of a reaction is proportional to rate of collision of reactants.
Thus with an increase in concentration of reactants , the rate of reaction also increases. This is because if the concentration of reactants increases , the chances of collision between molecules also increases and thus more products wil be formed which in turn increases the rate of reaction.
The metric system is used because it is based on the number 10. Ten is easy to use for mathematical operations and conversions.
It is also easy to use for scientific notation when you are referring to powers of ten. There are extremely large and extremely small numbers in science. Thus, scientific notation allows for accurate abbreviated ways to symbolize these numbers. For instance, if I were to say 1,000, in scientific notation it would be 1 x 10 ^3. If I was to say 1,000,000, I would scientifically write 1 x 10 ^6.
Orbital diagram:
<h3>Explanation</h3>
Fluorine F is found in the second column from the right end of a modern periodic table. Fluorine is next to and on the left of the noble gas element neon. A neutral fluorine atom is one electron short of neon, which contains 8 electrons in the outermost shell when neutral. As a result, there are 7 electrons in the outermost shell of a fluorine atom.
Fluorine is in period 2. Its electrons occupy two main shells. The second main shell is the outermost shell of F. There are two subshells in the second main shell:
- 2s, which holds up to two electrons, and
- 2p, which holds up to six electrons.
A 2s electron carries less energy than a 2p electron. By Aufbau principle, the seven electrons will fill the two spaces in 2s before moving on the 2p. Among the 7 outermost shell electrons, 
will end up going to 2p.
The only 2s orbital is filled with two electrons. The two 2s electrons will pair up with opposite spins, as seen with the two arrows. Two of the 2p orbitals will contain two electrons. Those electrons will also pair up. The third 2p orbital will contain only one electron. That electron can spin either 
or 
. Here that electron is shown as an upward arrow.
