On June 21, as seen from the North pole ...

-- the sun has been up, and it's been light outside,
for the past three months ... ever since March 21 .

-- The sun won't set, and it won't be dark outside,
for another three months ... until September 21.

-- Here at the North pole, it stays daylight for six months straight.
Today, on June 21, we're exactly halfway through the period of
continuous daylight.

7 0

3 years ago

If I started with 42.00 L of oxygen (O2) gas, how many grams is that?

belka [17]

Answer:

42 liters of oxygen (liquid) weighs 47900 grams.

Explanation:

5 0

3 years ago

1. Discuss briefly system and surrounding using suitable examples, highlighting heat transfers. 14 marks

lisabon 2012 [21]

A system is a part of the physical universe defined arbitrarily for observation purposes.

Boundaries are a part of the physical universe that are around the system.

In a scientific sense, a system is a part of the physical universe whose boundaries, that is, the limit between the system and its surroundings, are defined arbitrarily for observation purposes.

A system contains at least a model, represented in a phenomenological way, and it can be isolated (no mass nor energy interactions), closed (no mass interactions) or open.

The surroundings are a part of the physical universe that are around the system.

An example is a coffee-maker, where coffee-maker the system and air represents the surroundings, the coffee-maker receives energy from a heat source to warm up itself and releases part of such energy to the air.

We kindly invite to check this question on systems and surroundings: brainly.com/question/6044762

3 0

2 years ago

Describe a method to calculate the average atomic mass of the sample in the previous question using only the atomic masses of li

alexira [117]

Answer:

Explanation:

To calculate their average atomic masses which is otherwise known as the relative atomic mass, we simply multiply the given abundances of the atoms and the given atomic masses.

The abundace is the proportion or percentage or fraction by which each of the isotopes of an element occurs in nature.

This can be expressed below:

RAM = Σmₙαₙ

where mₙ is the mass of isotope n

αₙ is the abundance of isotope n

for this problem:

RAM of Li = m₆α₆ + m₇α₇

m₆ is mass of isotope Li-6

α₆ is the abundance of isotope Li-6

m₇ is mass of isotope Li-7

α₇ is the abundance of isotope Li-7

3 0

3 years ago