Just divide the two (2 / 0.05) and you will get your answer; there are 40 drops of bloodin the collection tube.
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
Read more at; brainly.in/question/17990661
Answer:
M of Al=33.09g or 0.0331kg
Explanation:
Heat Energy= specific heat*mass*change in temperature
H=M*C*T
make M subject of the formula
M=H/CT
M=685J/0.90J/g°C*(45°C-22°C)
M=685J/0.90J/g°C*23°C
M=685J/20.7J/g
M=33.09g or 0.0331kg
Carbon has 4 valence electrons, oxygen has 6