<u>Given:</u>
Volume of Na2CO3 = 250 ml = 0.250 L
Molarity of Na2CO3 = 6.0 M
Volume of CaF2 = 750 ml = 0.750 L
Molarity of CaF2 = 1.0 M
<u>To determine:</u>
The mass of CaCO3 produced
<u>Explanation:</u>
Na2CO3 + CaF2 → CaCO3 + 2NaF
Based on the reaction stoichiometry:
1 mole of Na2CO3 reacts with 1 moles of Caf2 to produce 1 mole of caco3
Moles of Na2CO3 present = V * M = 0.250 L * 6.0 moles/L = 1.5 moles
Moles of CaF2 present = V* M = 0.750 * 1 = 0.750 moles
CaF2 is the limiting reagent
Thus, # moles of CaCO3 produced = 0.750 moles
Molar mass of CaCO3 = 100 g/mol
Mass of CaCO3 produced = 0.750 moles * 100 g/mol = 75 g
Ans: Mass of CaCO3 produced = 75 g
Answer:
It is a law because it is a statement of fact that does not need any more experimental support.
Explanation:
A hypothesis is an acceptable assumption that is formulated through the collection of information and data and that attempts to explain some phenomenon. In other words, a hypothesis is a conjecture with which one tries to explain an observed fact. The formulation of a hypothesis can be derived in two different ways: by generalization, from a certain number of cases or observed phenomena; and, by analogies observed in the occurrence of different phenomena.
A theory is something that attempts to explain some phenomenon and that is accepted as true by the scientific community. In other words, a theory is a set of rules that describe the behavior of a particular system.
A law is a statement that expresses the constant relationships between phenomena of nature, society or the mind. Scientific law can be defined as an invariable relationship of terms. In other words, a law is what is scientifically proven to be true, it is universally applicable.
So scientific theories and scientific laws are based on hypotheses. But a theory is the explanation of an observed phenomenon, while a scientific law is the description of an observed phenomenon.
The movements of bodies in space are governed by Newton's Laws. These are laws why they are demonstrated by mathematical formulas and Universal application.
Then, the correct option is <u><em>"It is a law because it is a statement of fact that does not need any more experimental support."</em></u>
Most tornadoes happen in the midwest
Answer: 733 kcal
Explanation:
According to a system used to calculate the available energy of foods, we have the following data:
- protein has 4 kcal/g
- carbohydrates has 4 kcal/g
- fat has 9 kcal/g
- alcohol has 7 kcal/g
So, we are told Jhon and his wife's dinner has:
- 55 g of carbohydrates
- 36 g of protein
- 27 g of fat
- 18 g of
Now we have to multiply these values by the kilocalories:
- (55 g of carbohydrates)(4 kcal/g)=220 kcal
- (36 g of protein)(4 kcal/g)=144 kcal
- (27 g of fat)(9 kcal/g)=243 kcal
- (18 g of alcohol)(7 kcal/g)=126 kcal
Then we have to sum all, giving the following result:
<h2>733 kcal</h2>
the answer is A.) because the scientific method is used to answer problems.
This is the steps,
STEP 1: ask a question
STEP 2: state your hypothesis
STEP 3: conduct an experiment
STEP 4: analyze your results
STEP 5: make a conclusion