Complete question is;
A drop of water has a volume of approximately 7 × 10⁻² ml. How many water molecules does it contain? The density of water is 1.0 g/cm³.
This question will require us to first find the number of moles and then use avogadro's number to get the number of water molecules.
<em><u>Number of water molecules = 2.34 × 10²¹ molecules</u></em>
We are given;
Volume of water; V = 7 × 10⁻² ml
Density of water; ρ = 1 g/cm³ = 1 g/ml
Formula for mass is; m = ρV
m = 1 × 7 × 10⁻²
m = 7 × 10⁻² g
from online calculation, molar mass of water = 18.01 g/mol
Number of moles(n) = mass/molar mass
Thus;
n = (7 × 10⁻²)/18.01
n = 3.887 × 10⁻³ mol
from avogadro's number, we know that;
1 mol = 6.022 × 10²³ molecules
Thus,3.887 × 10⁻³ mol will give; 6.022 × 10²³ × 3.887 × 10⁻³ = 2.34 × 10²¹ molecules
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0.012moldm⁻³
Explanation:
Given parameters:
Mass of AgNO₃ = 1000mg
Volume of water = 500mL
Unknown:
Molarity of solution = ?
Solution:
The molarity of a solution is the number of moles of a solute dissolved in volume of solvent.
Molarity = 
Number of moles of AgNO₃ = ?
Number of moles = 
Molar mass of AgNO₃ = 108 + 14 + 3(16) = 170g/mol
convert mass to g;
1000mg = 1g
Number of moles = 
= 0.00588moles
convert the given volume to dm³;
1000mL = 1dm³;
500mL = 0.5dm³
Now solve;
Molarity = 
= 0.012moldm⁻³
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Molarity brainly.com/question/9324116
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Answer:
high ph -basic,low pH -acidic
Explanation:
hi I'm from India nice to meet you
Answer:
A.'C
Explanation:
Please answer my question
Answer:
Explanation:
To calculate their average atomic masses which is otherwise known as the relative atomic mass, we simply multiply the given abundances of the atoms and the given atomic masses.
The abundace is the proportion or percentage or fraction by which each of the isotopes of an element occurs in nature.
This can be expressed below:
RAM = Σmₙαₙ
where mₙ is the mass of isotope n
αₙ is the abundance of isotope n
for this problem:
RAM of Li = m₆α₆ + m₇α₇
m₆ is mass of isotope Li-6
α₆ is the abundance of isotope Li-6
m₇ is mass of isotope Li-7
α₇ is the abundance of isotope Li-7
