Answer:
The mass number of an isotope is indicated in the name of the isotope by writing the name of the element followed by a hyphen and the mass number.
Explanation:
Examples include carbon-14, uranium-235, and oxygen-17.
According to the Big Bang Theory, the Universe is expanding, hence option A is correct
<h3>What is the Big Bang theory?</h3>
Big Bang Theory is a theory about the origin and the nature of the universe and the earth we live in.
According to the theory, the universe started at an energized tiny point and exploded with a great force.
Learn more about the Big Bang Theory here:
brainly.com/question/17209127
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Answer:
1. Ice at 0 degrees C.
2. N₂ at STP.
3. N₂ at STP.
4. Water vapor at 150 degrees C and 1 atm.
Explanation:
First, we need to remember that entropy (S) is a <em>measure of how spread out or dispersed the energy of a system is among the different possible ways that system can contain energy</em>. The greater the dispersal, the greater is the entropy.
When the temperature is increased, the energies associated with all types of molecular motion increase. Consequently, the entropy of a system always increases with increasing temperature.
With this in mind, we consider the pairs:
1. Since the ice at 0ºC has a greater temperature than the ice at -40 ºC, the first has the higher entropy.
2. The N₂ at STP (that is, 1 atm and 25 ºC) has higher entropy than N₂ at 0ºC and 10 atm because it has a higher temperature and less pressure, which allows a greater dispersal of energy by the molecules of the gas.
3. The N₂ at STP has a higher entropy since it has a higher temperature than N₂ at 0ºC, even though it the first has a lower volume (24,4 L vs. 50 L).
4. The water vapor at 150 ºC and 1 atm have a higher temperature and a lower pressure. This means that its molecules will have an increased molecular motion than the molecules of water vapor at a lower temperature and higher pressure. Therefore, the first has the highest entropy.
Answer:
51.859 grams
Explanation:
Given:
Mass of sugar in the crunch cereal per serving= 11.0 grams
Mass of cereal served per serving = 60.0 grams
Molar mass of the sugar (C₁₂H₂₂O₁₁) = ( 12 × 12 + 22 × 1 + 16 × 11 ) = 342 grams
Number of moles of sugar per serving = Mass / Molar mass
= 11.0 / 342
= 0.03216 moles
Now,
0.03216 moles sugar requires 60 grams cereal
for 0.0278 moles of sugar, cereal required = (60 / 0.03216) × 0.0278
or
for 0.0278 moles of sugar, cereal required = 51.859 grams
<u>Ans: Mass of NaNO3 = 574 g</u>
<u>Given:</u>
Volume of NaNO3, V = 4.50 L
Molarity of NaNO3, M = 1.50 M i.e. 1.50 moles/L
Molar mass of NaNO3 = 85.00 g/mol
<u>To determine:</u>
The mass of NaNO3
<u>Explanation:</u>
Molarity of a solution can be expressed as the number of moles of the solute in a liter volume of solution
Molarity of NaNO3 = moles of NaNO3/volume of solution in L
1.50 moles/L = moles/4.50 L
moles NaNO3 = 1.50 *4.50 = 6.75 moles
Now, moles of NaNO3 = mass of NaNO3/molar mass NaNO3
mass of NaNO3 = moles * molar mass =
= 6.75 moles * 85.00 g/mole
= 573.75 g = 574 g
