Answer:
Before "true" labor begins, you might have "false" labor pains, also known as Braxton Hicks contractions.
Explanation:
Answer: 43.3 l
Explanation:
1) Chemical equation:
2 Li(s) + 2 H₂O (l) → 2LiOH(aq) + H₂ (g)
2) Mole ratios:
2 mol Li : 2 mol H₂O : 2 mol LiOH : 1 mol H₂
3) Number of moles of Li that react
n = mass in grams / atomic mass = 24.6g / 6.941 g/mol = 3.54 moles
4) Yield
Proportion:
2 mol Li / 1 mol H₂ = 3.54 mol Li/ x
⇒ x = 3.54 mol Li × 1 mol H / 2 mol Li = 1.77 mol H₂
4) Ideal gas equation
PV = nRT ⇒ V = nRT / P
V = 1.77 mol × 0.0821 [atm×l / (mol×K)] × 301 K / 1.01 atm = 43.3 l
V = 43.3 l ← answer
The total atomic number must be the same on each side. The total mass number must be the same on both side.
<span>On the RHS, for the mass number, we have 257 + 4 = 261 (the 4 comes from the 4 neutrons). That means the mass number of the missing piece on the LHS is 261 - 247 = 14. </span>
<span>One the RHS, for the atomic number we have a total of 104 since the 4 neutrons are all neutral. On the LHS, we have this: 104 - 98 = 6. </span>
<span>The missing piece is a nucleus of carbon 14. Done in your style, it is 14/6C</span>
Answer:
nerve cell, nervous tissue, brain, nervous system, human.
Explanation:
The order is from the simplest to the most complex, within the simplest would be the cellular structure, then the organs come, then systems (a set of organs in multidirectional operation among them) and finally the human, which is a set of systems .
Answer:
23.2 mols
Explanation:
(23.2 mol H2)(2 mol H2O) /(2 mol H2) = 23.2 mol H2O
you have to do stoichiometry - so start of with what you are given, which is 23.2 mols of hydrogen, then to cancel out mols of hydrogen, divide by what is in the equation: so 23.2 mols H2 / 2 mols H2. Next, to get mols of H2O multiply that number by the mols of water in the equation.
this answer makes sense because as you can see in the equation, there are 2 H2:2 H2O, so the amounts should be the same.
hope this helps! make sure to practice because it is ESSENTIAL that you understand this, especially if you plan on taking ap chem. good luck! :)
