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SHO18
Pre-Medical student that needs help sometimes
x^2-7x+15 factor help?
1 個解答Homework Help7 年前Chemistry help What is the value of x?
Washing soda, a compound used to prepare hard water for washing laundry, is a hydrate, which means that a certain number of water molecules are included in the solid structure. Its formula can be written as Na2CO3⋅xH2O, where x is the number of moles of H2O per mole of Na2CO3. When a 2.814−g sample of washing soda is heated at 25 ∘C, all the water of hydration is lost, leaving 1.04g of Na2CO3.
What is the value of x?
Chemistry7 年前How many moles of KBr are present in 200mL of a 0.285M solution?
How many moles of KBr are present in 200mL of a 0.285M solution? I wasn't in class and i don't know how to set up or solve this problem can anyone help me?
2 個解答Chemistry8 年前Formula Weight for chemistry?
Nitrous oxide, N2O, known as laughing gas and used as an anesthetic in dentistry.
Express your answer using three significant figures.
2 個解答Chemistry8 年前Ca^2+ and ClO3^- Express your answer as a chemical formula.?
the 2+ is a superscript, and the 3 is a subscript while the negative sign is a superscript
2 個解答Chemistry8 年前Which of the following would you expect to be a molecule and which would you expect to be part of an ionic sol?
Which of the following would you expect to be a molecule and which would you expect to be part of an ionic solid? CO,HBr,LiBr,SrO,NO,BaS,LiCl,RbCl
3 個解答Chemistry8 年前How many atoms are in the following?
Carbon atoms- C2H5COOH3
Oxygen atoms- Ca(C104)2
Hydrogen- (NH4)2HPO4
2 個解答Chemistry8 年前What is a radius of rhodium atom in angstroms (A)?
Part A
What is the radius of a rhodium atom in angstroms? Express your answer using two significant figures.
Part B
What is the radius of a rhodium atom in meters? Express your answer using two significant figures.
Part C
How many Rh atoms would have to be placed side by side to span a distance of 3.5 mu m ?
Express your answer using two significant figures.
Part D
If the atom is assumed to be a sphere, what is the volume in m^3 of a single Rh atom?
Express your answer using two significant figures.
1 個解答Chemistry8 年前Gold can be hammered into extremely thin sheets called gold leaf. An architect wants to cover a 100 ft\,?
Gold can be hammered into extremely thin sheets called gold leaf. An architect wants to cover a 100ft X 84ft ceiling with gold leaf that is five-millionths of an inch thick. The density of gold is 19.32g/cm^3, and gold costs $ 953 per troy ounce (1 troy ounce = 31.1034768g}). How much will it cost the architect to buy the necessary gold? Express your answer using one significant figures.
2 個解答Chemistry8 年前chem help Gen chem 121?
The density of air at ordinary atmospheric pressure and 25 C is 1.19 g/L. What is the mass, in kilograms, of the air in a room that measures 13.5 X 19.5 X 7.0ft? Express your answer using two significant figures.
1 個解答Chemistry8 年前The speed of light is 3.00 times 10^8 m/s. How long does it take for light to travel from Earth to the Moon?
and back. Its a chem problem and i need a little bit of help
4 個解答Physics8 年前