Answer:
¹⁶⁸₇₉Au
Explanation:
The symbol of the atom is given as;
¹⁷²₈₁Tl
If undergoes a nuclear reaction and it ejects an alpha particle;
An alpha particle is the same as an helium atom
¹⁷²₈₁Tl → ₂⁴H + ₐᵇK
K is the hypothetical symbol of the new atom
b is the new mass number
a is the new atomic number;
Conserving mass number;
172 = 4 + b
b = 172 - 4 = 168
Conserving atomic number;
81 = 2 + a
81 - 2 = a
a = 79
The new compound is gold with a symbol of;
¹⁶⁸₇₉Au
Answer: The time period of about 1 msec after an action potential before another one can be initiated -----b
Explanation:Absolute refractory period is the time after an action potential onset when no amount or how strong a stimulus is can cause a second action potential. it is always the time period of 1 m sec between an initiated action potential and an impending next initiated one with the the maximum firing frequency at about 1000 impulses per second.
The absolute refractory period is as a result of molecular processes that triggers the action potential known as sodium channels(tiny pore nerves) . Now the sodium channels exist in three states which are open, close and inactivated states. At rest, the sodium channel is closed, but when a there is an electrical stimulation, the sodium channel opens up to respond to that stimulus which after it passes to the inactivated state, in which the the spores are closed and no matter how strong or the amount an impending next stimulus is, will not cause the pore to open until it has recovered and returned back to the closed state.
Answer:
3.98g
Explanation:
Given parameters:
Number of molecules = 1.2 x 10²⁴ molecules
Unknown:
Mass of H₂ = ?
Solution:
To find the mass of this molecule, we use the expression below:
Mass = number of moles x molar mass
Molar mass of H₂ = 2(1) = 2g/mol
6.02 x 10²³ molecules are contained in 1 mole of a substance
So; 1.2 x 10²⁴ molecules will have 
= 1.99 moles of H₂
Mass of H₂ = 1.99 x 2 = 3.98g
Answer: b. It would happen faster at warmer air temperatures
Explanation:saw another site say this was the answer
An element is composed of a single type of cell. So we can expect only one kind of element. For example if it is a carbon element it will contain only carbon atoms.
