Answer:
6.022 × 10²² atoms
Explanation:
Generally 1 mol of any element contains 6.02×10^23 atoms. The number 6.022 × 10²³ is known as Avogadro's number.
Mass of Aluminium = 2.70g
Molar mass = 27g/mol
Number of moles = Mass / Molar mass = 2.70 / 27 = 0.1 mol
1 mol = 6.022 × 10²³
0.1 mol = x
x = 6.022 × 10²³ * 0.1 = 6.022 × 10²² atoms
Answer:
so 0.15 moles X 22.4 dm3/mole=3.36 dm3. Next we find the moles of hexane combusted, and then the moles of CO2. Finally, we find the volume of CO2 using the fact that at STP, 1 mole of gas = 22.4 dm3.
The answer is: D.unstable nuclei emitting high-energy particles as they formed more stable compositions.
Those high-energy particles are alpha particles
, beta particles
, gamma radiation.
For example, the decay chain of ²³⁸U is called the uranium series.
Decay start with U-238 and ends with Pb-206. There are several alpha and beta minus decays.
Antoine Henri Becquerel (1852 – 1908) was a French physicist and the first person to discover evidence of radioactivity.
Becquerel wrapped fluorescing crystal (uranium salt potassium uranyl sulfate) in a cloth, along with the photographic plate and a copper Maltese cross.
Several days later, he discovered that a image of the cross appeared on the plate.
The uranium salt was emitting radiation.
Because of this discovery, Becquerel won a Nobel Prize for Physics in 1903, which he shared with Marie Curie and Pierre Curie.
Answer:
Zn + CuSO4 —> ZnSO4 + Cu
Explanation:
Zn is higher than Cu in electrochemical series and so will displaces Cu in solution according to the equation:
Zn + CuSO4 —> ZnSO4 + Cu
One way of expressing concentration is by percent. It may be on the basis of mass, mole or volume. Percent is expressed as the amount of solute per amount of the solution. For this case, we are given the percent by mass. In order to solve the amount of solute, we multiply the percent with the amount of the solution.
Mass of solute = percent by mass x mass solution
Mass of solute = 0.0350 x 2.50 x10^2 = 8.75 grams of solute
