How Many Atoms Are in a Drop of Mercury That

question 13

Multiple Choice

How many atoms are in a drop of mercury that has a diameter of 1.0 mm? (Volume of a sphere is 4πr³/3; density of mercury = 13.6 g/cm³)

• A)2.1 × 10 ¹⁹
• B)1.7 × 10 ²⁰
• C)2.1 × 10 ²²
• D)1.7 × 10 ²³
• E)None of these choices are correct.

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Definitions:

Fetoscopy

A technique that uses a small camera, inserted through a small incision on the mother’s abdomen or cervix and placed into the amniotic sac, to examine and perform procedures on the fetus during pregnancy.

Chorionic Villus Sampling

A prenatal test in which a sample of chorionic villi from the placenta is removed and tested for genetic abnormalities.

Noninvasive Prenatal Testing

A method to screen for certain genetic conditions in a fetus using maternal blood sample without risk to the fetus.

Ultrasound

A medical imaging technique that uses high-frequency sound waves to produce images of structures within the body, commonly used in prenatal care.