No' of molecules divide by avogadro number , 6×6.023×10^23 so (2.2×10^22)÷(6.023×10^23)
= 0.03653 moles
moles × Molar mass = mass
n×Mr=m
0.03653×40 = 1.46 grams
Answer:
The atomic number of burienium will be 307.
Explanation:
During positron emission proton is converted into the neutron and one electron neutrino with positron is released. It means the atomic number will be reduce by one and atomic mass remain same.
For example:
²³Mg₁₂ → ₁₁Na²³+ e⁺+ Ve
Similarly, when highlinium-308 undergoes positron emission the new element burienium is produced and the atomic number will be 307 while atomic mass remain same.
Properties of beta radiations:
Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.
The mass of beta particle is smaller than the alpha particles.
They can travel in air in few meter distance.
These radiations can penetrate into the human skin.
The sheet of aluminium is used to block the beta radiation
Answer:
Qm = -55.8Kj/mole
Explanation:
NaOH(aq) + HNO₃(aq) => NaNO₃(aq) + H₂O(l)
Qm = (mc∆T)water /moles acid
Given => 100ml(0.300M) NaOH(aq) + 100ml(0.300M)HNO₃(aq)
=> 0.03mole NaOH(aq) + 0.03mole HNO₃(aq)
=> 0.03mole NaNO₃(aq) + 0.03mole H₂O(l)
ΔH⁰rxn = [(200ml)(1.00cal/g∙°C)(37 – 35)°C]water / 0.03mole HNO₃
= 13,333 cal/mole x 4.184J/cal = 55,787J/mol = 55.8Kj/mole (exothermic)*
Heat of reactions comes from formation of H-Oxy bonds on formation of water of reaction and heats the 200ml of solvent water from 35⁰C to 37⁰C.
Use the periodic table , it should be the long decimal if u look it up
Answer: Identifies the number of protons a single atom of the element contains.
Explanation: The atomic number helps people identify elements according to the number of protons one atom of the element has. It essentially defines the element. While having a neutral charge, it also provides the number of electrons the element has (in one atom).
