The same number of valence electrons exists in the same family of elements in the periodic table. In finding the answer to this problem, we just have to find the pair that belongs to the same family in the periodic table. The same family means same column. Among these, Oxygen and lead (Pb) are in the same family. This pair is the answer.
Forces affect how objects move. They may cause motion; they may also slow, stop, or change the direction of motion of an object that is already moving. Since force cause changes in the speed or direction of an object, we can say that forces cause changes in velocity. Remember that acceleration is a change in velocity. Let’s say an object is moving along a table on earth, suddenly the finite table ends, resulting in the object being present in the air, which means there is no normal contact force N to combat the force by gravity mg, which is why there is an acceleration downwards. This proves as a projectile motion since the direction of motion start changing from horizontal to vertical. Another example is one throwing an object up. It moves up and slows down, reaching its maximum point, leading to it starting to move downwards. This too is a change in motion.
Answer:
Explanation:
Take a random sample of nuts from the jar. Let's take two handfuls, after shaking the jar and mixing the nuts thoroughly. Separate the nuts into almonds and cashews. Count each pile, then do the following calculation (these numbers are random, for example only).
<u> Count</u> <u>Percentage %</u>
Almonds 38 (38)/(87)x100
Cashews <u> 49</u> 49/87x100
87 87/87 = 100%
Ratio of Almonds to Cashews: <u>38/49</u>
Answer:
The boiling point is 308.27 K (35.27°C)
Explanation:
The chemical reaction for the boiling of titanium tetrachloride is shown below:
Ti
⇒ Ti
ΔH°
(Ti
) = -804.2 kJ/mol
ΔH°
(Ti
) = -763.2 kJ/mol
Therefore,
ΔH°
= ΔH°
(Ti
) - ΔH°
(Ti
) = -763.2 - (-804.2) = 41 kJ/mol = 41000 J/mol
Similarly,
s°(Ti
) = 221.9 J/(mol*K)
s°(Ti
) = 354.9 J/(mol*K)
Therefore,
s° = s° (Ti
) - s°(Ti
) = 354.9 - 221.9 = 133 J/(mol*K)
Thus, T = ΔH°
/s° = [41000 J/mol]/[133 J/(mol*K)] = 308. 27 K or 35.27°C
Therefore, the boiling point of titanium tetrachloride is 308.27 K or 35.27°C.
<span>The reason it will be 7 for some titrations is that when you titrates a strong acid with a strong base for example HCl and NaOH the salt formed is conjugate base of strong acid and will be a very weak base
That means that it cannot produce any OH^-1 and all the H+ has been converted to water.The only source of H+ or OH is water with a Ka of 10^-14 so the pH = -log [H+]=-log 10^-7 = 7
second reason is
When you titrates a weak acid with strong base at equivalence point
only a water solution of the conjugate base exists
CH3COOH + NaOH ----- Na+ CH3COO^-1 + H2O
Since the conjugate base is the conjugate base of a weak acid it will hydrolyze in water like so
for instance Na+ CH3COO^-1 + HCl---- CH3COOH + NaCl the equivalence point will be way BELOW 7 and in the case of above will be less than 5. So pH of 7 at equivalence point is only reached in strong acid strong base titrations.
hope this helps</span>