Answer is B.
As the diaphragm contracts and flattens, it increases the volume of the thorax where the lungs are located. This results in a decrease in pressure (Boyle’s Law, if you know it) that creates a pressure gradient from outside to inside. This is what causes air to move into the lungs.
Answer:
2Fe + 3H2SO4 + Fe2(SO4)3+ 3H2
Explanation:
1. Fe (SO4) 3 is an incorrectly written formula because iron is trivalent as we can see by this three ahead of SO4. SO4 is divalent always.
2. since (SO4) is 3, this three shows us that there must be 3 in the reactants as well.
so now there is 3H2SO4
3. Since we have added 3 to one hydrogen we must add another. So now it's 3H2
4. and finally iron. In Fe2 (SO4) 3 we see this 2 in front of Fe which means it goes 2Fe.
Answer:
Element symbol Cu
Number of protons 29
Number of electrons 28
Explanation:
To get the element symbol, we need the name of the element. To correctly identify the name of the element, we need the proton number.
Now the mass number is 65 and the number of neutrons is 36. The number of protons is this the mass number minus the number of neutrons. This equals 65 - 36 = 29 protons.
The element with 29 protons is copper Cu.
Now to get the number of electrons, for an electrically neutral atom , the number of electrons equals the number of protons. But here, the atom is not electrically neutral anymore as it has now formed a univalent positive ion of +1.
To form a positive ion, you have to do so by losing electrons. The atom in question here has just lost one electron. Thus, our of the 29, it is left with only 28 electrons.
Answer: It takes 3.120 seconds for the concentration of A to decrease from 0.860 M to 0.260 M.
Explanation:
Integrated rate law for second order kinetics is given by:
k = rate constant = 
= initial concentration = 0.860 M
a= concentration left after time t = 0.260 M
Thus it takes 3.120 seconds for the concentration of A to decrease from 0.860 M to 0.260 M.
