The bond between one water molecule and another is called a hydrogen bond.  It is stronger than the bond between other polar molecules because the hydrogen 'end' of the molecule has a very small electron cloud and is a positive pole of the molecule which forms a strong attraction to the negative end of a neighboring … Read more

2 Mg + O₂ ---> 2 MgO is a combination reaction

You are missing information.  With what you give it is possible to calculate the mass of the solution: 1.002 g/mL  x  9.86 mL  = 9.88 g of solution.  You need to know the molarity of the solution to do any more than that.

The molar mass of KCl is 74.6 g  multiply that by 2.45 and you get 182.8 g which is the amount you would need to make 1000 mL of solution.  Divide that by 20 to get the amount for 50 mL because 50 is 1/20 of 1000.  9.14 g is needed.

Molar mass of K₂S is 110.3 g multiply that by 2.18 and you get 240.5 g to make one liter. Your proportion is 240.5g   =      200.0 g     Divide 200.0 by 240.5 = 0.832 liters    1 liter   x

You have 15.0 g of methanol in 125 g of solution.  Percent would be the amount in 100g of solution.  Your proportion looks like this:   15.0g    =    x     x = 12.0% 125.0 g   100.0 g

It is an ionic compound.  All ionic compounds are solid at room temperature and are water soluble.

1750 g/ 55.847 g per mole = 31.34 moles

It has a low molecular mass: 17  and weaker intermolecular hydrogen bonds than water which is a liquid at room temperature while NH3 is a gas.

Na2CO3   +   2 HCl  -->  2 NaCl  + H2O  + CO2 H2O  + CO2  starts out as carbonic acid-  H2CO3 -  (carbonation) and decomposes to water and carbon dioxide which is what makes the bubbles in soda.

It means the atoms are lined up in such a way as to create a magnetic field loop that exits from one side or end of the substance and reenters at the opposite side or end.

Chalk powder is insoluble in water so the easiest way would be to filter the mixture or just let the water evaporate.

2 Na  + O2 --> Na2O2 3.74 g Na x  1 mol Na / 23.0g x 1 mol Na2O2 / 2 mol Na   x  78.0g Na2O2 /1 mol Na2O2 =  6.34 g Na2O2 = theoretical yield    5.34 g = actual yield so  5.34/6.34  x 100 = 84.2%

Ammonia is made of 2 elements, Nitrogen and Hydrogen.  It is not on the periodic table of elements because it is a compound and not an element.

These are the halogens: Fluorine, Chlorine, Bromine, Iodine and Astatine

Francium

K3po4

Hydrogen chloride is a gas that dissolves in water to produce hydrochloric acid.  That makes it a toxic gas.

There are two ways atoms join to make compounds:  Metal atoms can give up electrons to non metals.  This causes the metal atoms to become negative ions and the non metal atoms to become positive ions. Since opposite charges attract each other the ions stick together to form a new substance and the bond type is called … Read more