Answer:
The correct answer is - Mosquitoes transmit the virus as parasites which feed on the blood of host organisms and inject the virus during feeding.
Explanation:
According to the CDC, the seasonal West Nile virus is caused by the mosquitoes of freshwater transmit this disease to humans and others. These mosquitoes are feed on the birds and pick these viruses.
These viruses stick on mosquitoes and when they feed on the blood of humans they transmit these viruses by injecting viruses into the blood of humans.
<u>Analysing the Question:</u>
We are given a 250 mL solution of 0.5M K₂Cr₂O₇
Which means that we have:
0.5 Mole in 1L of the solution
0.125 moles in 250 mL of the solution <em>[dividing both the numbers by 4]</em>
<em />
<u>Mass of K₂Cr₂O₇ in the given solution:</u>
Molar mass of K₂Cr₂O₇(Potassium Dichromate) = 194 g/mol
<em>we know that we have 0.125 moles in the 250 mL solution provided</em>
Mass = Number of moles * Molar mass
Mass = 0.125 * 194
Mass = 36.75 grams
Answer:
Explanation:
Given that,
The mass of the rock, m = 15 g
The volume of the rock, V = 10 cm³
We need to find the density of the rock. The density of an object is equal to the mass per unit volume such that,
So, the density of the rock is equal to .
Ppm = mass of solute mg / mass of solvent kg
0.008 * 1000 = 8.0 mg ( solute )
1000 / 1000 = 1.0 kg (solvent )
ppm = 8 / 1
= 8.0 ppm
hope this helps!