It takes so much heat to melt ice or evaporate water because extra energy is required to break the hydrogen bonds between water molecules.
<h3>
Hydrogen bond</h3>
Hydrogen bonding is an electrostatic force of attraction between a hydrogen atom found between a pair of other atoms having a high affinity for electrons.
Hydrogen bonds cause water to be exceptionally attracted to each other creating cohesion.
It takes so much heat to melt ice or evaporate water because extra energy is required to break the hydrogen bonds between water molecules.
Find out more on Hydrogen bond at: brainly.com/question/12798212
A: C₆H₁₂O₆ + 6H₂O + 6O₂
6CO₂ + 12H₂O = C₆H₁₂O₆ + 6H₂O + 6O₂
<u>Answer:</u> The magnitude rating for an earthquake causing an amplitude 10,000,000 times
is 7.
<u>Explanation:</u>
Richter scale is defined as the scale which expresses the magnitude of earthquake on the basis of the seismograph oscillations.
The equation used to measure the magnitude of an earthquake on Richter scale is:

where
I = amplitude registered on seismograph 100 km away from seismic center = 
= small amplitude
Putting values in above equation, we get:

Hence, the magnitude rating for an earthquake causing an amplitude 10,000,000 times
is 7.
Answer:
2.67 × 10⁻²
Explanation:
Equation for the reaction is expressed as:
CaCrO₄(s) ⇄ Ca₂⁺(aq) + CrO₂⁻⁴(aq)
Given that:
Kc=7.1×10⁻⁴
Kc= ![[Ca^{2+}][CrO^{2-}_4]](https://tex.z-dn.net/?f=%5BCa%5E%7B2%2B%7D%5D%5BCrO%5E%7B2-%7D_4%5D)
Kc= [x][x]
Kc= [x²]
7.1×10⁻⁴ = [x²]
x = 
x = 0.0267
x = 
The correct answer is:
A positively charged nucleus is surrounded by one or more negatively charged electrons
The explanation:
when:
proton is a positively charged elementary particle that is a fundamental constituent of all atomic nuclei.
neutron is a subatomic particle found in the nucleus of every atom except that of simple hydrogen. The particle derives its name from the fact that it has no electrical charge
electron is a negatively charged subatomic particle. It can be either free (not attached to any atom), or bound to the nucleus of an atom .
so, , there are positively charged protons and zero-charged neutrons in the nucleus of an atom. Therefore, the nucleus is positively charged, Surrounding the nucleus, the electrons have negative charge.
Thus, the correct answer is (3): A positively charged nucleus is surrounded by one or more negatively charged electrons is correct.