Answer:
Large-scale natural disasters
Explanation:
The emergency situation that rescue workers could be in that would make it difficult for them to get energy to their electrical devices is "Large-scale natural disasters"
Large-scale natural disasters are very destructive and devastating. Their impact and effect can range from destruction of infrastructures, properties, social amenities and even ecosystems. When such disasters break out, they destroy things and which leads to difficulty in accessing certain amenities. Rescue workers even find it difficult to access energy for their electrical devices - because there is power outage.
Some of these large-scale natural disasters are earthquakes, tornadoes, hurricanes, floods, etc.
The density of He is 1.79 x 10⁻⁴ g/mL
In other words in 1 mL there's 1.79 x 10⁻⁴ g of He.
To fill a volume of 6.3 L the mass of He required
= 1.79 x 10⁻⁴ g/mL * 6300 mL
= 11 277 * 10⁻⁴ g
Therefore mass of He required = 1.1277 g of He
Answer
Do you think that the mole should be considered a base unit in the SI system?
The mole is not a base unit on a par with the six property base units; it cannot be used in significant physical–chemical comparisons until the subscript parameter p in mole-of-Ep has been given a certain “value”."
Explanation:
The primary greenhouse gases are water vapor, carbon dioxide, methane, nitrous oxide, and ozone. So, the correct answer among these options is water vapor, that is considered to be a greenhouse gas.
The average mass of an atom is calculated with the formula:
average mass = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2) + ... an so on
For the boron we have two isotopes, so the formula will become:
average mass of boron = abundance of isotope (1) × mass of isotope (1) + abundance of isotope (2) × mass of isotope (2)
We plug in the values:
10.81 = 0.1980 × 10.012938 + 0.8020 × mass of isotope (2)
10.81 = 1.98 + 0.8020 × mass of isotope (2)
10.81 - 1.98 = 0.8020 × mass of isotope (2)
8.83 = 0.8020 × mass of isotope (2)
mass of isotope (2) = 8.83 / 0.8020
mass of isotope (2) = 11.009975
mass of isotope (1) = 10.012938 (given by the question)
