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# what particle has a mass of approximately one atomic mass unit? (answer)

The atomic weight of hydrogen is 1.008 amu, and we know that it has one electron and one proton. Electrons are much smaller than protons, so the inference is that the proton weight must be closer to 1 amu than the electron.

# How to simplify this? (answer)

Nisya, We can re-write the question as 1/(ax - b)1/2 - ((ax - b)1/2)/b and then perform subtraction using the LCM of b(ax-b)1/2. We then get the fraction (b - ax +b)/ (b(ax-b)1/2) or (2b - ax) / (b(ax-b)1/2). Hope this helps.

# How many electrons will be transferred from Mg to SO4 to form MgSO4? (answer)

Nat, Magnesium has the atomic number 12. There are 12 electrons in the outermost shell. Mg atom would look like  this Mg: (if we ignore the full shells). This molecule is very reactive, as it wants to reach a full shell, and it can do that by losing those two electrons. When magnesium...

# x = y/(y^2 - 16), solve for y (answer)

Sometimes the answer is not well defined, like in this case. This problem may be solved by the quadratic method, like Kirill did, or by completing the square for y2 - y/x, by adding and subtracting 1/4x2. The problem then reduces to   (y2 - y/x + 1/4x2) -16 - 1/4x2 = 0, or (y - 1/2x)2...

# i am having trouble with this (answer)

Crystal, This problem is a variant on y = mx + c. You have P = 5.9t – 11,706, with y being P, m = 5.9, x = t and c = -11706.    To evaluate P for t = 1985 and 2000, substitute these values in the equation to get the values of P (in percent). The values are ~ 5 and 94.   Looking at the...

Erica,    One way to visualize the function is to assume values for x and see the values of y that are derived. The function is y2 = 3x2 -4x -8. For x = 0, y2 = -8. Here the answer is not a real number.  If x = 1, y2 = 3-4-8 = -9; again not a real number. If x = 3, y2 = 27-12-8...

# x = 4, y = 12 (answer)

If y varies directly as x, then y must be a function of x, or y = a * x. Looking at the values of y (12) and x (4), and putting them in the equation y = ax, we get 12 =a*4 ,  or a = 3. hence y = 3x must be the the equation that relates x and y.

# Calculate concentrations in air, water and octanol (answer)

Using Henry's Law, we get the partial pressure of the gas above the solution as p = 0.2 (atm M-1)  * 0.1 (g) / 106.2 (g/mole) * 1/1 (L) , since total volume of liquid is 1L. This value of p is transferred to the gas equation PV = (g/M)RT to determine the weight g of xylene in the headspace...