Answer:
11 electrons
Explanation:
The atomic number of sodium is 11. This tells us that sodium has 11 protons and because it is neutral it has 11 electrons. The mass number of an element tells us the number of protons AND neutrons in an atom (the two particles that have a measurable mass).
Answer:
The concentration the student should write down in her lab is 2.2 mol/L
Explanation:
Atomic mass of the elements are:
Na: 22.989 u
S: 32.065 u
O: 15.999 u
Molar mass of sodium thiosulfate, Na2S2O3 = (2*22.989 + 2*32.065 + 3*15.999) g/mol = 158.105 g/mol.
Mass of Na2S2O3 taken = (19.440 - 2.2) g = 17.240 g.
For mole(s) of Na2S2O3 = (mass taken)/(molar mass)
= (17.240 g)/(158.105 g/mol) = 0.1090 mole.
Volume of the solution = 50.29 mL = (50.29 mL)*(1 L)/(1000 mL)
= 0.05029 L.
To find the molar concentration of the sodium thiosulfate solution prepared we use the formula:
= (moles of sodium thiosulfate)/(volume of solution in L)
= (0.1090 mole)/(0.05029 L)
= 2.1674 mol/L
when forces are balanced the object does not move.
Explanation:
if you and your friend push both sides of the chair at the same time with the same amount of strength the chair wouldn't move.
Answer:
계란은 확실히 닭보다 먼저 나왔지만 닭 계란은 그렇지 않았습니다. 그러나 진화론적 증거에 따라 절대적으로 한 편을 선택해야 한다면 우리는 팀 에그에 있습니다..
Explanation:
도움이 되었기를 바랍니다..
미리 환영합니다!!
(;ŏ﹏ŏ)(ㆁωㆁ)
