Dec 29, 2016 · 68%= 17/25 68% = 68/100" "larr find the HCF to simplify 68/100 (div4)/(div4) = 17/25 This is now the simplest form because there are no other common factors (except for 1) Algebra Science

Jul 18, 2016 · So #2n+2# is the next even number. Thus #2n+(2n+2)=68# So #4n+2=68# Subtract 2 from both sides #4n=66# #n=66/4=16.5 larr" seed value"# Thus the 1st even number is #2n->2xx16.5=33# Thus the next even number is #33+2=35# #color(blue)(33+35 = 68)#.~~~~~ #color(blue)("Solution for two consecutive odd numbers sum to 68")# Using the notation from the ...

Jul 16, 2018 · See a solution process below: Because the ratio of students who voted for the winner compared to all students who voted is 0.88 we can rewrite this as: 0.88 = 88/100 And, because we know the total number of students who voted is 75 and if we call the number of students who voted for the winner s, we can then write this relationship and solve for s: 88/100 = s/75 color(red)(75) xx 88/100 ...

Oct 28, 2016 · There must be 68 neutrons in a ""^118Sn isotope. The mass number relates to the massive particles: protons, and neutrons. Since there are 50 protons, there MUST be 68 neutrons. Note that an examiner would be quite justified in asking you this question WITHOUT advice as to Z, the atomic number, if tin metal were specified. Do you agree?

Jul 25, 2017 · There is "0.0301 mol Fe" in "1.68 g Fe". There are 1.81xx10^22 atoms in "1.68 g Fe". Divide the mass of iron by its molar mass in g/mol to get the moles of iron. (1.68color(red)cancel(color(black)("g Fe")))/(55.845color(red)cancel(color(black)("g Fe"))/"mol Fe")="0.0301 mol Fe" One mole of anything is 6.022xx10^23 of anything, including atoms. Multiply mol Fe by (6.022xx10^23)/("mol"). 0 ...

Nov 26, 2015 · 69 At first glance, it may seem like the problem didn't provide you with enough information. However, if you have access to a periodic table, you can determine the mass number of the second isotope by examining its atomic mass. So, the key to this problem is the fact that gallium has two isotopes. This means that the percent abundances of these two isotopes must amount to 100%. This means that ...

Dec 29, 2015 · "M"_r (Ga) = 69.7231 " to 4 decimal places". To find the average atomic mass ("A"_r) of an element, given the percentage rarities of its isotopes, simply multiply each isotope's "A"_r by its percentage that is expressed as a decimal and total the results. We can carry this out in a single line of working: "M"_r ("Ga") = (68.9256 * 0.60108) + (70.9247 * 0.39892) "M"_r ("Ga") = 69.7231 " to 4 ...

Jul 3, 2015 · x/2 We can represent a number in general by x. Halving a number means dividing it by two, so the expression that shows the half of a number is x/2, since you divide a number by two.

May 25, 2017 · 1.26 xx 10^20 "atoms" In one mole of any substance there are 6.022 xx 10^23 units of that substance. (This number is called Avogadro's number, N_"A".) We need to convert the mass of silicon to moles using the molar mass of silicon, 28.06 "g"/"mol". This number means that one mole of pure silicon would have a mass of 28.06 "g".

May 28, 2018 · See below Rounding to the nearest unit means to find the nearest integer to a given number. Basically, you have to get rid of the decimal part, if any. As an immediate corollary, you have that if a number x is already an integer, then there's no point in rounding it, since the result would be x itself. Now, let's assume that our number actually has a decimal part, for example 4.687. It might ...