Explanation:
been defined in such a way. It is defined as the numbers of particles in 12 g of 12C. If it were 24 g instead of 12 g, then the weight of 1 mole of substance would equal 2 times the atomic/molecular mass in grams.
Answer:
The correct answer is hydrogen.
Explanation:
Stars in the main sequence will remain in the main sequence as long as their cores contain hydrogen atoms. This is because main sequence stars run on the hydrogen atoms within their core to prevent them from falling to the force of gravity. Once these hydrogen atoms run out, the star is no longer considered a main sequence star, gravity takes hold, and the star collapses.
Answer:
108.6 g
Explanation:
- 2NaN₃(s) → 2Na(s) + 3N₂(g)
First we use the <em>PV=nRT formula</em> to <u>calculate the number of nitrogen moles</u>:
- R = 0.082 atm·L·mol⁻¹·K⁻¹
- T = 0 °C ⇒ 0 + 273.2 = 273.2 K
<u>Inputting the data</u>:
- 1.00 atm * 56.0 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 273.2 K
Then we <u>convert 2.5 moles of N₂ into moles of NaN₃</u>, using the <em>stoichiometric coefficients of the balanced reaction</em>:
- 2.5 mol N₂ *
= 1.67 mol NaN₃
Finally we <u>convert 1.67 moles of NaN₃ into grams</u>, using its <em>molar mass</em>:
- 1.67 mol * 65 g/mol = 108.6 g
Answer:
3.2 cm X 2.8 cm X 2.6 cm/ 1 cube - not exact
1 mL - exact
1 cm³ - exact
12 cubes/ 1 tray - exact
268.8 mL/tray - not exact
Explanation:
We can use the picture attached below to solve this problem. The first part is not exact because Sally is using a ruler to measure the cube which would have a margin of error, regardless of how small. The 
is exact, since that is the actual accurate exchange. Next, since there are 12 cubes in a single ice tray this measurement is also exact. Lastly, since Sally's initial measurement of the cubes is not exact, then the final calculated value will also not be exact.
Answer:
# 5
Explanation:
The question describes silver being "poured" into a mold and cools to become a solid bar. This is the phase of liquid to solid. When a element cools down below it's freezing points to become a solid.
<u>Liquid to Solid Definition:</u>
Freezing, or solidification, is a phase transition in which a liquid turns into a solid when its temperature is lowered to or below its freezing point. All known liquids, except helium, freeze when the temperature is low enough.
