Answer:
Explanation:
The question is asking to write the <em>isotopic symbol </em>of the form 
for the <em>sodium isotope with 13 neutrons</em>.
In general, the isotopic symbol in the given form shows:
- The element's chemical symbol: X
- A: mass number of the isotope, written as a superscript to the left of the element's simbol, and
A = number of protons + number of neutrons
- Z: atomic number of the isotope, written as a subscript to the left of the elements's symbol,
Z = number of protons
The atomic symbol of sodium is Na.
The atomic number, or number of protons, is the same for every isotope of the element, and you can find it in any periodic table. Tha atomic number of sodium is 11. Thus:
The mass number is the number of protons plus neutrons, hence:
Now you can write the isotope symbol for the sodium isotope with 13 neutrons:
An mL is also equivalent to cm³, signifying that 140 mL is equivalent to 140 cm³. The mass of ethanol is calculated by multiplying the density by the volume.
mass = (140 cm³)(0.789 g/cm³)
mass = 110.46 g
Then, calculate the number of moles of ethanol by dividing the mass by the molar mass of ethanol equal to 46.07 g/mol.
number of moles = (110.46 g/ 46.07 g/mol) = 2.4 mol
Then, multiply the number of moles by the Avogadro's number.
2.4 mol (6.022 x 10²³)
<em> number of molecules = 1.445 x 10²⁴</em>
Answer:
Something defined as hydrophilic is actually attracted to water, while something that is hydrophobic resists water.
Explanation:
I hope it's help u :)
Answer:
I believe the answer isT 2.
Explanation:
he formula for IMA of a first-class lever is effort-distance/resistance-distance.
Answer: Because it's a combination of chemicals, vodka doesn't freeze at the same temperature as either water or alcohol. Of course, vodka will freeze, but not at the temperature of an ordinary freezer. This is because vodka contains enough alcohol to lower the freezing point of water below the -17°C of your typical freezer.
Explanation: .......
