Different forms of matter have different melting/boiling points. For example, at 100 degrees Celsius, H2O (water) will turn from lliquid to gas. But NaOH (table salt) doesn't even go from solid to liquid until some 800 degrees Celsius. So, in order to figure out which state matter is at 35 Celsius, you'd have to be more specific about what kind of matter...
The volume of the buffer solution having a ph value is calculated by henderson's hasselbalch equation.
Buffer solution is water based solution which consists of a mixture containing a weak acid and a conjugate base of the weak acid. or a weak base and conjugate acid of a weak base.it is a mixture of weak acid and a base. The pH of the buffer solution is determined by the expression of the henderson hasselbalch equation.
pH=pKa + log [salt]/[acid]
Where, pKa =dissociation constant , A- = concentration of the conjugate base, [HA]= concentration of the acid. Here, a buffer solution contains 0.403m acetic acid and 250 ml is added in order to prepare a buffer with a ph of 4.750. Putting all the values in the henderson hasselbalch equation we find the pH of the buffer solution.
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Answer:
The two valid principles are:
- Scientific theories can be replaced by better theories.
- An experiment can disprove a theory that scientists have accepted.
Explanation:
The scientific knwoledge is not inmutable; it may (and does) change with new discoveries.
In fact, scientific theories cannot be proved right, instead they are constantly tested to try to disprove them. This is what the principle that theories are falsiable means.
As long as a scientific theory is not disproved it remains valid, but new discoveries may lead, eventually, to its disprovement.
Scientific knowledge evolves because new procedures, new technologies, and new evidence leads to a better understanding and better explanations.
Answer:
partial pressure of gas D Pd = 15.5 kPa
Explanation:
As per the Dalton's law of partial pressure, in a mixture, pressure exerted by each gas when summed gives the total partial pressure exerted by mixture.
P(Total) = P1+P2+P3.....
Given P(Total) = 35.7 kPa
Partial pressure of gas A Pa = 7.8 kPa
Partial pressure of gas B Pb = 3.7 kPa
Partial pressure of gas C Pc = 8.7 kPa
There, Partial pressure of gas D Pd = P(Total) -(Pa+Pb+Pc)
Pd = 35.7-(7.8+3.7+8.7) = 35.7-20.2 kPa = 15.5 kPa
Therefore, partial pressure of gas D Pd = 15.5 kPa
Reaction equation:
Al(OH)₃ + 3HCl → AlCl₃ + 3H₂O
Moles of Al(OH)₃:
moles = mass/Mr
= 1.51 / (27 + 17 x 3)
= 0.019
Molar ratio Al(OH)₃ : HCl = 1 : 3
Moles of HCl required = 0.019 x 3
=0.057
concentration = moles/volume
volume = 0.057 / 0.1
= 0.57 dm³
= 570 ml