t<135 because it will be less then 135°
Answer:
1 million years
Explanation:
The half life of a radioactive isotope refers to the time it takes for the radioactive isotope to decay to half of its original amount.
The half life of a radioactive isotope is independent of the amount of starting material. Hence, whether the amount of starting material is small or large, the half life of the substance remains the same.
Hence the half life of 2 green marbles and 500,000 green marbles is 1 million years.
Answer:
Explanation:
a) The mass of the reactants is 2.36 grams, and the mass of the products is 1.57 grams plus the mass of the carbonic acid. Thus, using the law of conservation of mass, we get the mass of the carbonic acid is 2.36 - 1.57 = 0.79 grams.
b) The gram-formula mass of sodium bicarbonate is 84.006 g/mol, meaning that 2.36/84.006 = 0.028 moles were consumed. Thus, this means that in theory, 0.014 moles of carbonic acid should have been produced, which would have a mass of (0.014)(62.024)=0.868 grams. Thus, the percentage yield is (0.79)/(0.868) * 100 = 91%
Answer:
Explanation:
1.Scientists use a shared system for reporting measurements called the International System of Units (SI). We use common measurement systems because science involves a lot of replication to confirm results. The most common system used in science is the metric system.
2.m, kg, m^3
3. g value change
Explanation:
Ionic equation
NaCl(aq) --> Na+(aq) + Cl-(aq)
Na2SO4(aq) --> 2Na+(aq) + SO4^2-(aq)
In NaCl solution, 1 mole of Na+ is dissociated in 1 liter of solution while in Na2SO4, 2 moles of Na+ is dissociated in 1 liter of solution.
Molecular weight of NA2SO4 = (23*2) + 32 + (16*4)
= 142 g/mol
Molecular weight of NaCl = 23 + 35.5
= 58.5 g/mol
Masses
% Mass of NA+ in Na2SO4 = mass of Na+/total mass of Na2SO4 * 100
= 46/142 * 100
= 32.4%
% Mass of NA+ in NaCl = mass of Na+/total mass of NaCl * 100
= 23/58.5 * 100
= 39.3%
Therefore, the % mass of Na+ in NaCl and Na2SO4 are different so it cannot be used.
