Answer:
Mass of hydrogen gas produced = 0.2 g
Explanation:
Given data:
Number of moles of Mg = 0.2 mol
Number of moles of HCl = 0.2 mol
Mass of hydrogen gas produced = ?
Solution:
Chemical equation:
Mg + 2HCl → MgCl₂ + H₂
Now we will compare the moles of of hydrogen with Mg and HCl.
Mg : H₂
1 : 1
0.2 : 0.2
HCl : H₂
2 : 1
0.2 : 1/2×0.2 = 0.1
HCl produced less number of moles of hydrogen gas it will act as limiting reactant.
Mass of hydrogen:
Mass = number of moles × molar mass
Mass = 0.1 mol × 2 g/mol
Mass = 0.2 g
The age of the fossil given the present amount of Carbon-14 is given in the equation,
A(t) = A(o)(0.5)^t/h
where A(t) is the current amount, A(o) is the initial amount, t is time and h is the half-life. Substituting the known values to the equation,
A(t) / A(o) = 0.125 = (0.5)^(t/5730)
The value of t from the equation is 17190.
Thus, the age of the fossil is mostly likely to be 17190 years old.
Two moles because one moles would be 6.02×10 23 atoms 2 moles would equal twice that number of atoms
Drugs interfere with the way neurons send, receive, and process signals via neurotransmitters. Some drugs, such as marijuana and heroin, can activate neurons because their chemical structure mimics that of a natural neurotransmitter in the body. This allows the drugs to attach onto and activate the neurons. Although these drugs mimic the brain’s own chemicals, they don’t activate neurons in the same way as a natural neurotransmitter, and they lead to abnormal messages being sent through the network.
Other drugs, such as amphetamine or cocaine, can cause the neurons to release abnormally large amounts of natural neurotransmitters or prevent the normal recycling of these brain chemicals by interfering with transporters. This too amplifies or disrupts the normal communication between neurons.
