Fossils are fundamental to the geologic time scale. The names of most of the eons and eras end in zoic, because these time intervals are often recognized on the basis of animal life. Rocks formed during the Proterozoic Eon may have fossils of relative simple organisms, such as bacteria, algae, and wormlike animals

4 0

2 years ago

A 0.89% (w/v) sodium chloride solution is referred to as physiological saline solution because it has the same concentration of

maks197457 [2]

1) 0.89% m/v = 0.89 grams of NaCl / 100 ml of solution

=> 8.9 grams of NaCl in 1000 ml of solution = 8.9 grams of NaCl in 1 liter of solution

2) Molarity = M = number of moles of solute / liters of solution

=> calculate the number of moles of 8.9 grams of NaCl

3) molar mass of NaCl = 23.0 g /mol + 35.5 g/mol = 58.5 g / mol

4) number of moles of NaCl = mass / molar mass = 8.9 g / 58.5 g / mol = 0.152 mol

5) M = 0.152 mol NaCl / 1 liter solution = 0.152 M

Answer: 0.152 M

4 0

3 years ago

What is the molar mass of water in the hydrate? FeSO4 • 7H2O

Rainbow [258]

M=7M(H₂O)

M=7*18.015 g/mol = 126.105 g/mol

5 0

3 years ago