Answer: D. They are made up of hard spheres that are in random motion.
Explanation:
A gas is a <u>state of aggregation of matter</u> in which, under certain conditions of temperature and pressure, <u>its molecules interact weakly with each other, without forming molecular bonds</u>, adopting the shape and volume of the container that contains them and tending to separate everything possible because of its <u>high concentration of kinetic energy</u>.
The molecules of a gas are practically <u>free</u> and have the ability to be distributed throughout the space in which they are contained because <u>the gravitational forces and attraction between them are practically negligible</u> compared to the speed at which they move. .
Therefore, gas molecules do not travel specific trajectories or vibrate in a stationary position, instead <u>they move quickly and randomly through the entire space of the container that contains them.</u>
You did not include the questions.
I did some research and found the questions:
<span>
What is the mass of 1 mole of pennies?
How many moles of pennies have a mass equal to the mass of the moon?
Solutions:
1) mass of 1 mole of pennies
Data: mass of 1 penny = 2.50 g
1 mole = 6.022 * 10^ 23 units
Proportion:
1 penny 6.022 * 10^23 penny
-------------- = ----------------------------
2.50 g x
Solve: x = 6.022 * 10^23 penny * 2.50g / 1 penny = 15.055* 10^23
Since 2.50 has 3 significant figures, the answer must use 3 significant figures => x = 15.1 * 10^ 23 g = 1.51 * 10^24 g
Answer: 1 mol of pennies have a mass of 1.51 * 10^24 g
2) How many moles of pennies have a mass equal to the same mass of the Moon
Convert the mass of the Moon grams: 7.35 * 10^22 kg = 7.35 * 10^ 25 g
1 mol x
---------------------- = ----------------------
1.51 * 10^ 24g 7.35 * 10^ 25 g
=> x = 7.35 * 10^ 25 g * 1 mol / (1.51 * 10^24 g)= 48.7 mol
Answer: 48.7 mol
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Answer:
Option A
Explanation:
Number of millimoles of Na3PO4 = 1 × 100 = 100
Number of millimoles of AgNO3 = 1 × 100 = 100
When 1 mole of Na3PO4 is dissociated we get 3 moles of sodium ions and 1 mole of phosphate ion
When 1 mole of AgNO3 is dissociated, we get 1 mole of Ag+ and 1 mole of NO3-
As Ag+ concentration is negligible, the dissociated Ag+ ion must have form the precipitate with phosphate ion and as number of moles of Ag+ and phosphate ion are same, therefore the concentration of phosphate ion must be negligible
Here as 100 millimoles of Na3PO4 is there, we get 300 millimoles of Na+ and 100 millimoles of PO43-
And as 100 millimoles of AgNO3 is there, we get 100 millimoles of Ag+ and 100 millimoles of NO3-
∴ Increasing order of concentration will be PO43- < NO3- < Na+
Answer:
A. Reference blank
B. Cuvettes
C. Transmittance
D. Absorbance
E. Wavelength
Explanation:
A reference blank is a sample prepared using the solvent and any other chemicals in the sample solutions, but not the absorbing substance.
A square-shaped container, typically made of quartz, designed to hold samples in a spectrophotometer is known as Cuvettes.
A measurement of the amount of light that passes through a sample or percentage of light transmitted by the sample, with the respective intensities of the incident and transmitted beams is called Transmittance.
The measurement of the amount of light taken in by a sample is known as Absorbance
The wavelength is also the distance travelled by the wave during a period of oscillation. In spectrophotometry, the unit is inversely proportional to energy and commonly measured in nanometers
The location of the valence electron or the outermost electron is expressed in quantum numbers. There are five quantum numbers: prinicipal (n), angular momentum (l), magnetic (ms) and magnetic spin (ms) quantum numbers. This is based on Bohr's atomic model where electrons orbit around the nucleus. These electrons are in the orbitals with specific energy levels. Starting from energy level 1 that is closest to the nucleus, the energy level decreases to 2, 3, 4, 5, 6, and 7. These energy level numbers represent the principal quantum number. Within each orbital also contains subshell. From increasing to decreasing order, these subshells are the s, p, d and f subshells. These subshells represent the angular momentum quantum numer. Specifically, s=0, p=1, d=2 and f=3. Therefore, if the electron is in the orbital 5p, the quantum number would be: 5, 1. Applying these to the choices, the correct pairing would be:
2p: n=2. l=1
3d: n=3, l=2
2s: n=2. l=0
4f: n=4. l=3
1s: n=1, l=0
