Answer:
5 km = 3.107 miles
one Kilometer is equal to 0.621371 meters
so the equation is
5 km times 0.621371 m
is equal to 3.107
The atomic mass of the magnesium is : 24.31⋅g.
<h3>What is isotopes?</h3>
Isotopes are members of a family of elements that all have the same number of protons and different numbers of neutrons. The number of protons in the nucleus determines the atomic number of an element on the periodic table.
Magnesium has three natural isotopes: ²⁴Mg, ²⁵Mg, and ²⁶Mg.
<h3>What is atomic mass ?</h3>
Atomic mass is the mass of an atom. The SI unit of mass is the kilogram, while atomic mass is often expressed in the non-SI unit dalton (synonymous with uniform atomic mass unit). 1 Da is defined as 1/12 the mass of a free carbon-12 atom at rest in the ground state.
Calculation :
The atomic mass is the weighted average of the individual isotopic masses:
(23.99×78.99%+24.99×10.00%+25.98×11.01%)⋅g=24.31⋅g
To know more atomic mass please click here : brainly.com/question/338808
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I'm not understanding that much. but if i'm right the answer is <span>3.84 x 10^-19 J</span>
Answer:
a) The concentration of drug in the bottle is 9.8 mg/ml
b) 0.15 ml drug solution + 1.85 ml saline.
c) 4.9 × 10⁻⁵ mol/l
Explanation:
Hi there!
a) The concentration of the drug in the bottle is 294 mg/ 30.0 ml = 9.8 mg/ml
b) The drug has to be administrated at a dose of 0.0210 mg/ kg body mass. Then, the total mass of drug that there should be in the injection for a person of 70 kg will be:
0.0210 mg/kg-body mass * 70 kg = 1.47 mg drug.
The volume of solution that contains that mass of drug can be calculated using the value of the concentration calculated in a)
If 9.8 mg of the drug is contained in 1 ml of solution, then 1.47 mg drug will be present in (1.47 mg * 1 ml/ 9.8 mg) 0.15 ml.
To prepare the injection, you should take 0.15 ml of the concentrated drug solution and (2.0 ml - 0.15 ml) 1.85 ml saline
c) In the injection there is a concentration of (1.47 mg / 2.0 ml) 0.735 mg/ml.
Let´s convert it to molarity:
0.735 mg/ml * 1000 ml/l * 0.001 g/mg* 1 mol/ 15000 g = 4.9 × 10⁻⁵ mol/l