Answer:
Which of the following happens during a lunar eclipse?
Select one:
a. Earth casts a shadow on the moon.
<u>b. The moon casts a shadow on Earth.
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c. Earth stops revolving in its orbit.
d. Earth starts revolving around the moon.
Explanation:
Isotopes are elements with same atomic number but different mass number. Hydrogen and Deuterium are isotopes with same atomic number but different mass number. Hydrogen have atomic number 1 and mass number 1 where as deuterium have atomic number 1 but mass number 2
Answer:
Solution — Molar mass (Molecular mass in gram) of CaCO3 = 40+12+3×16 = 100 g No. of moles of CaCO3 = No. of molecules/Avogadro constant = 6.022 × 1023/ 6.022 × 1023 = 1 mole Mass of CaCO3 = No. of moles × molar mass = 1 × 100 g = 100 g.
Explanation:
Answer:
See explanation
Explanation:
What has happened to the nail is a typical example of a chemical change. In a chemical change, a new substance is formed, heat is released and it is not easily reversible.
The nail has undergone chemical change because it no longer conducts heat as it used to. This shows that the chemical composition of the nail has changed.
Also, the change in the physical appearance of the nail from a shinning metal to reddish brown indicates that a chemical change has occurred.
