Answer:
Scientific theories are testable and make falsifiable predictions. They describe the causes of a particular natural phenomenon and are used to explain and predict aspects of the physical universe or specific areas of inquiry (for example, electricity, chemistry, and astronomy).
A good theory in the theoretical sense is (1) consistent with empirical observations; is (2) precise, (3) parsimonious, (4) explanatorily broad, and (5) falsifiable; and (6) promotes scientific progress (among others; Table 1.1).
The correct answer is 30 seconds
Answer:
Gravity always pulls objects such as a desk, book or person down. Thus, when you jump gravity causes you to land on the ground. Friction, however, doesn't pull objects down
Since you know the ratio of atoms, you can start to put a formula togeter. The formula might look like:<span>
X<span>H2.67
</span></span>but since atoms can't come in fractional amounts, we have to multiply the formula by some number in order to turn 2.67 into a whole #, while still maintaining the ratio. Multiplying 2.67 by 3 yields 8, so the most likely ratio in the molecule is
X3H8<span>so the ratio of 1:2.67 is still maintained. The mass percent tells you that out of every 100g of compound, 91.26g is element X, so the other 8.74g must be H. Dividing each mass by the number of moles in the formula gets us the molar mass of each element (approximately). DIviding 8.74g by 8 gets 1.09, roughly the molar mass of hydrogen. Dividing 91.26g by 3 gets us 30.4, roughly the molar mass of phosphorus. Element X is most likely phosphorus</span>
The answer is a change in internal energy causes work to be done and heat to flow into the system.
<u>Explanation:</u>
- The first law of thermodynamics is a similar version of the law of conservation of energy where the energy can neither be created nor be destroyed, it can be transformed from one form to the other.
- It also defines that the work is done and heat flowing into the system is due to the change in internal energy. The sum of all energy including kinetic and potential energy except the displaced energy to the surrounding is known as internal energy.
- ΔU represents the change in internal energy of the system, Q represents the net heat transferred into the system, and W represents the net work done by the system. So +ve Q adds energy to the system and =ve W takes energy from the system. Thus ΔU=Q−W.
