Answer:
(a) 13.7 g.
(b) 28.91 g.
Explanation:
- molality (m) is the no. of moles of solute dissolved in 1.0 kg of solvent.
∴ m = (no. of moles of solute)/(mass of water (kg))
<em>∴ m = (mass/molar mass of solute)/(mass of water (kg)).</em>
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<u><em>(a) Calculate the mass of CaCl₂·6H₂O needed to prepare 0.125 m CaCl₂(aq) by using 500. g of water.</em></u>
∵ m = (mass/molar mass of CaCl₂·6H₂O)/(mass of water (kg)).
m = 0.125 m, molar mass of CaCl₂·6H₂O = 219.0757 g/mol, mass of water = 500.0 g = 0.5 kg.
∴ 0.125 m = (mass of CaCl₂·6H₂O / 219.0757 g/mol)/(0.5 kg).
∴ mass of CaCl₂·6H₂O = (0.125 m)(219.0757 g/mol)(0.5 kg) = 13.7 g.
<u><em>(b) What mass of NiSO₄·6H₂O must be dissolved in 500. g of water to produce 0.22 m NiSO₄(aq)?</em></u>
∵ m = (mass/molar mass of NiSO₄·6H₂O)/(mass of water (kg)).
m = 0.22 m, molar mass of NiSO₄·6H₂O = 262.84 g/mol, mass of water = 500.0 g = 0.5 kg.
∴ 0.125 m = (mass of NiSO₄·6H₂O / 262.84 g/mol)/(0.5 kg).
∴ mass of NiSO₄·6H₂O = (0.22 m)(262.84 g/mol)(0.5 kg) = 28.91 g.
The solution that conducts electricity and has a pH value of 7 would most likely be a neutral solution. Water is among the best examples of a neutral solution. When the pH of a solution is considered to be lesser than 7, it is an acid, while if the pH is greater than 7, it is considered to be a basic solution.
Answer:
Introduction to Basic Microscopy. Microscopes are specialized optical instruments designed to produce magnified visual or photographic (including digital) images of objects or specimens that are too small to be seen with the naked eye.
Microscope are the important tools which are used by scientist. For example, in material science, medicine, mineralogy and microbiology.
Light microscope is able to send light. Light is being focused in a tight breath whereby that light passes through a sample which later it is able to create an image. This image passes to different lenses which magnifies it until it reaches the camera.
There are different types of microscope for example, Compound light microscope, Simple light microscope, and monocular microscope.
In simple light microscope only one lens which which is being used to magnify an object and it is not able to reach to a higher magnification.
In compound light microscope it uses two lenses to produce image. For example eyepiece lens and objective lens.
Explanation:
Answer:
The mass of one mole of a substance is equal to that substance's molecular weight. ... water is 18.015 atomic mass units (amu), so one mole of water weight 18.015 grams. ... Avogadro's number is a proportion that relates molar mass on an atomic ... one molecule of water (H2O), one mole of oxygen (6.022×1023 of O atoms)