Hi!
To convert grams to moles, you need to divide the amount (grams) of your substance by its molar mass, both of which are given to you.
28 g CaO / 58.08 g/mol CaO = 0.4820936639 moles of CaO
(And 28 contains two significant digits, so you will round this to 0.48 moles.)
Good luck!
Answer:
cosmic radiation
Explanation:
Radiation from space is called cosmic radiation, which is constantly hitting the Earth
Tin to Fluorine mass ratios:
1) For compound A:
38.5/12.3
= 3.13
2) For compound B:
56.5/36.2
= 1.56
The lowest whole number mass ratio is 2. It cannot be 1 because it is less than that required for compound B.
The image, blanks and options are missing in the question. So the image is attached below and the complete question is:
Describe the celestial object in the image.
The object is called________ a because it is producing _______ and has not yet ________ .
First Blank: A.Meteor B.Meteorite C.Meteoroid
Second Blank: A. a streak of light B. An orange Horizon C. A star- Filled sky
Third Blank: A. Reached earths atmosphere B. Struck Earth C. Completed an orbit
Answer:
First Blank - A. Meteor
Second Blank - A. a streak of light
Third Blank - A. Reached earths atmosphere
Explanation:
The given image shows celestial object called meteor.
The meteor is often called shooting star as it produces a streak of light. When a meteoroid reaches Earth's atmosphere, it experiences a friction which allows the meteoroid to burn up and produce a streak of light in the sky.
Hence, the correct answer for blanks is Meteor, a streak of light and Reached earths atmosphere.
Answer:
B. II.
Explanation:
The idea of recrystallization works when the solubility of the target substance decreases as the temperature of the solution decreases.
The method of recrystallization involves dissolving the solute in a suitable hot solvent and then allow the solution to cool gradually. The pure solute dissolves in the hot solvent and then separates out of the solution as it is cooled to room temperature.
Hence recrystallization is preferred over solvent extraction when the desired compound is poorly soluble in the solvent pair at low temperatures and greatly soluble in the solvent pair at high temperatures.
