<span>The magnetic field of the Earth serves a useful purpose in deflecting Solar radiation. Without the magnetic field there is much more charged-particle radiation striking the surface. The auroras would occur everywhere instead of at the magnetic poles. Compass needles wouldn't work, and then they would flip direction.. The magnetic field IS DECREASING and could go to zero and reverse sometime in the next few tens-of-thousands of years.</span>
Answer:
ok so first of all try working hard then ill answer u
Explanation:
T = 20 % : 20 / 100 = 0.2
m1 = solute
m2 = Solvent
T = m1 / m1 + m2
0.2 = 500 g / 500 g + m2
0.2 * ( 500 + m2 ) = 500
0.2 * 500 + 0.2 m2 = 500
100 + 0.2 m2 = 500
0.2 m2 = 500 - 100
0.2 m2 = 400
m2 = 400 / 0.2
m2 = 2000 g of water
hope this helps!
Answer:
The correct answer is: pH= 4.70
Explanation:
We use the <em>Henderson-Hasselbach equation</em> in order to calculate the pH of a buffer solution:
![pH= pKa + log \frac{ [conjugate base]}{[acid]}](https://tex.z-dn.net/?f=pH%3D%20pKa%20%2B%20log%20%20%20%5Cfrac%7B%20%5Bconjugate%20base%5D%7D%7B%5Bacid%5D%7D)
Given:
pKa= 4.90
[conjugate base]= 4.75 mol
[acid]= 7.50 mol
We calculate pH as follows:
pH = 4.90 + log (4.75 mol/7.50 mol) = 4.90 + (-0.20) = 4.70
Answer:
group two elements are called alkaline earth metals
Explanation:
Because their oxides form in the earth and are water soluble
