Me mememememememememememememememememeememememeemememememememe
An atomic mass unit is defined as a mass equal to one twelfth the mass of an atom of carbon-12. The mass of any isotope of any element is expressed in relation to the carbon-12 standard. For example, one atom of helium-4 has a mass of 4.0026 amu. An atom of sulfur-32 has a mass of 31.972 amu.
Answer:
biosphere
Explanation:
Living things need water (hydrosphere), chemicals from the atmosphere, and nutrients gained by eating things in the biosphere.
The purpose of using distilled water in the cuvette of the spectrophotometer is to calibrate the instrument. It is generally considered that distilled water shows zero absorbance and 100 % transmittance. So, to zero out the absorbance of compounds other than the analyte being determined, distilled water is used as a blank.
If the unknown being determined is prepared using ethanol as the base solution, the blank used must be ethanol. This is because absorbance if any from the solvent, ethanol must be zeroed out as when the measurement of the actual unknown is being made, the absorbance of the solvent does not interfere.
Answer: 0.24 moles
Explanation:
Molecular Mass of NaCl (23 + 35.5) = 58.5g
58.5g of Sodium Chloride -------> 1 mole of NaCl
∴ 13.8g of Sodium Chloride ------> 1 ÷58.5 x 13.8 = 0.2358974 ≈ 0.24moles
-
