Answer:
physical
Explanation:
you have to do it ur self
Atomic theory is the scientific inquiry of the nature of matter, which is subject to change as new information is discovered. The answer is A.
<span>It verifies the significant relationships of the observed and hypothesized variables in the study.
Furthermore, the authors utilize and make use of the scientific method in order to have clear basis and evidence for their investigations. Research method is always used to answer every scientific inquiry and in gaining evidential data or knowledge. The scientific method has the following process or at least undergoes the process of
1. Observation</span>
2. Hypothesis
3. Experimentation
4. Interpretation of data
5. Evaluating the data
6. Passing and recording the data
<span>These steps are crucial and the empirical data that these scientists obtain are very important to keep that is why research paper, thesis and dissertations exists.<span>
</span></span>
144 mL of fluorine gas is required to react with 1.28 g of calcium bromide to form calcium fluoride and bromine gas at STP.
<h3>What is Ideal Gas Law ? </h3>
The ideal gas law states that the pressure of gas is directly proportional to the volume and temperature of the gas.
PV = nRT
where,
P = Presure
V = Volume in liters
n = number of moles of gas
R = Ideal gas constant
T = temperature in Kelvin
Here,
P = 1 atm [At STP]
R = 0.0821 atm.L/mol.K
T = 273 K [At STP]
Now first find the number of moles
F₂ + CaBr₂ → CaF₂ + Br₂
Here 1 mole of F₂ reacts with 1 mole of CaBr₂.
So, 199.89 g CaBr₂ reacts with = 1 mole of F₂
1.28 g of CaBr₂ will react with = n mole of F₂

n = 0.0064 mole
Now put the value in above equation we get
PV = nRT
1 atm × V = 0.0064 × 0.0821 atm.L/mol.K × 273 K
V = 0.1434 L
V ≈ 144 mL
Thus from the above conclusion we can say that 144 mL of fluorine gas is required to react with 1.28 g of calcium bromide to form calcium fluoride and bromine gas at STP.
Learn more about the Ideal Gas here: brainly.com/question/20348074
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After 3 years, the substance will go through 4 half lives. You can do 230*(1/2)^4, which is 14.375.