Answer:
1.2×10²³ atoms.
Explanation:
Data obtained from the question include:
Mole of propanone = 0.20 mole
Number of atoms of propanone =.?
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.022×10²³ atoms.
This implies that 1 mole of propanone also contains 6.022×10²³ atoms.
Thus, we can obtain the number of atoms in 0.20 mole of propanone as illustrated below:
1 mole of propanone contains 6.022×10²³ atoms.
Therefore, 0.20 mole of propanone will contain = 0.2 × 6.022×10²³ = 1.2×10²³ atoms.
Thus, 0.20 mole of propanone contain
1.2×10²³ atoms.
Answer:
a . knowledge and existing theories .
b. falsifiable scope
Answer:
Gallium-72
Explanation:
The elements are identified by the number of protons of the atom, which is its atomic number.
In this case the number of protons 39 (atomic number 39) permit you to identify the element as gallium.
Now, to identify the isotope you tell the name of the element and add the mass number.
The mass number is the sum of the protons and the neutrons
In this case, the number of neutrons is the original 39 plus the 2 added suddenly, i.e. 39 + 2 = 41, so the mass number is 31 + 41 = 72
Therefore, the isotope is gallium - 72.
Answer:
526g is the mass of this sample
Explanation:
To solve this question we must, as first, find the <em>molar mass </em>of Al₂(Cr₂O₇)₃ using the periodic table. The molar mass is defined as the mass of this compound per mole. With this value we can find the mass in 0.750 moles as follows:
<em>Molar mass Al₂(Cr₂O₇)₃</em>
2Al = 2*26.98g/mol = 53.96g/mol
6 Cr = 6*51.9961g/mol = 311.9766g/mol
21 O = 21*15.999g/mol = 335.979g/mol
53.96g/mol + 311.9766g/mol + 335.979g/mol
= 701.9156g/mol
The mass of 0.750 moles is:
0.750 moles * (701.9156g / mol) =
<h3>526g is the mass of this sample</h3>
Answer:
potassium hydroxide + sulfuric acid → potassium sulfate + water.
Explanation:
Hope it helps.. if yes, plz mark me as brainliest