Question 2 2 points)
Which of the atoms shown has an atomic number of 42
1
2
4
7
Answer:
4 is the answer
Explanation:
i am not sure for this question
When drawing a Bohr model for Sulfur, how many energy levels will you
draw?
5
4
3
2.
Answer:
3
Explanation:
2,8,6
Oxygen and hydrogen are both elements that are found as gases at room temperature. When oxygen combines with hydrogen, they produce the compound water according to the chemical equation below.
O2 + 2 H2 2 H2O
Water is a liquid at room temperature. This example shows that in a chemical equation, the substance that is produced
A.
has properties that are different from the original substances.
B.
can only contain a single type of element.
C.
contains fewer types of elements than the original substances.
D.
always has the same properties as the original substances.
Answer:
A
Explanation:
has properties that are different from the original substances.
Answering the following questions will help you focus on the outcomes of the experiments.
Experiment 1:
1. What happens to the water in the small tube as the water in the test tube absorbs heat?
2. Why do you think a small tube was used to observe the expansion of water?
Experiment 2:
1. Compare the circumference of the balloon before and after freezing. What is the percent increase in this
measurement?
Combined Results
Write a summary paragraph discussing this experiment and the results. Use the following questions and topics to help
guide the content of your paragraph.
Summarize the conclusions that you can draw from this experiment. Use the questions above to guide your ideas.
2. Summarize any difficulties or problems you had in performing the experiment that might have affected the results.
Describe how you might change the procedure to avoid these problems.
3. Describe at least two real-world issues or examples that illustrate the findings of this experiment.
WRITER
Word Count: of 400
OVERALL SCORE:
Answer:
ex.1
1.The water in the test tube expands as it is heated. There is only one direction to expand in, the glass tube. This glass tube is narrow so that a small change in volume will result in a considerable change in height; your signal is amplified. This is the same phenomenon as in thermometers with a glass bulb on the lower end.
2. there will be a thermal expansion will happened.
The breakdown of a certain pollutant X in sunlight is known to follow first-order kinetics. An atmospheric scientist studying the process fills a 20.0Lreaction flask with a sample of urban air and finds that the partial pressure of X in the flask decreases from 0.473atm to 0.376atm over 5.6hours.
Calculate the initial rate of decomposition of X, that is, the rate at which Xwas disappearing at the start of the experiment.
Round your answer to 2 significant digits.
Answer:
0.019 atm / hr
Explanation:
Initial Concentration (Pressure) [A]o = 0.473 atm
Final Concentration (Pressure) [A] = 0.376 atm
Time = 5.6 hours
The breakdown follows first order kinetics.
The integrated rate law for a first order reaction is given as;
ln[A] = ln[A]o - kt
ln(0.376) = ln(0.473) - k (5.6)
ln(0.376) - ln(0.473) = - 5.6 k
5.6 k = 0.23
k = 0.0411 hr⁻¹
The rate of decomposition is given as;
Rate = k [X]
Where [X] represents Concentration (Pressure) = 0.473 atm
Rate = 0.0411 * 0.473 = 0.019 atm / hr
Move the red warning icon to focus of the earthquake.
Move the green location icon to the epicenter of the earthquake.
Move the blue star icon to the fault.
Answer:
Red goes in the spiky yellow box. Green goes where the red circles are. Blue goes in the small yellow box that is pointing to the line.
Explanation:
The focus of an earthquake is where it starts in the earth. The epicenter is the part directly above the focus on the surface. The fault is the part where the earth's crust splits.
Write the line notation for a cell in which the cell reaction is as follow
H2 + I2 = 2 HI
Answer:
I2(g)/I^-(aq)//H2 (g)/H^+(aq)
Explanation:
Let us remember that in every redox reaction, a specie is oxidized and a specie is reduced.
This means that one specie looses electrons while the other species gains electrons.
Considering the overall reaction; H2 + I2 = 2 HI
Oxidation half equation;
H2 (g) ------> 2H^+(aq) + 2e
Reduction half equation;
I2(g) + 2e ------> 2I^-(aq)
Line notation;
I2(g)/I^-(aq)//H2 (g)/H^+(aq)
What is the molecular weight of magnesium chloride?
Answer:
Magnesium chloride/Molar mass
95.211 g/mol
Explanation:
Jane is sitting in the family car. Her mother is driving her from their house to the library. Jane waves as she passes her friend Marina. Which of the following is not moving with respect to Jane?
A. Marina
B. The family car
C.The library
D. Jane’s house
Answer:
B) The family car
Explanation:
I hope this helps :)
Steam is collected and observed to condense into liquid water. Which of the following would you expect to observe if a thermometer recorded the temperature of the substance?
SELECT AN ANSWER
The temperature would decrease.
The temperature would remain the same.
It would depend on the amount of steam.
The temperature would increase.
the water will be increased
Which of the following are true about an atom? Choose all that apply.
Answer:
Explanation:
Atoms are the building blocks of matter.
They are the smallest particles of an element that still have the element's properties.
All atoms are very small, but atoms of different elements vary in size.
Three main types of particles that make up all atoms are protons, neutrons, and electrons.
Which of the following statements correctly explain the relationship between the solubility of a gas and its pressure?
A. As pressure is increased, the rate at which gas molecules enter the solution decreases.
B. More gas molecules are soluble as pressure is increased.
C. The solubility of a gas decreases with a decrease in pressure.
D. The solubility of nitrogen gas at 2.00 atmatm is twice the solubility of the gas at 1.00 atmatm.
E. The concentration of gas particles in the solution is higher at 4.25 atmatm than at 1.00 atmatm.
F. Fewer gas molecules are soluble at higher pressures.
G. As pressure decreases, the concentration of gas molecules in the solution increases.
Answer:
B, C, D, E
Explanation:
According to Henry's law, as the pressure is increased, the solubility of a given gas increases. So, solubility is directly proportional to pressure.
Thus, the following statements are correct:
B. More gas molecules are soluble as pressure is increased.
Is correct because as the pressure is increased, the solubility increases.
C. The solubility of a gas decreases with a decrease in pressure.
Is correct because solubility and pressure are directly proportional: if the pressure is decreased, the solubility will be decreased.
D. The solubility of nitrogen gas at 2.00 atm is twice the solubility of the gas at 1.00 atm.
Is correct because 2.00 atm is twice 1.00 atm, so if the pressure is increased twice, the solubility is increased twice.
E. The concentration of gas particles in the solution is higher at 4.25 atm than at 1.00 atm.
Is correct because 4.25 atm>1.00 atm (the higher the pressure, the higher the solubility, and therefore the concentration of gas particles in solution).
The remaining options (A, G) are incorrect. They contradict Henry's law.
Explain the 3 steps required to determine the molecular formula.
Answer:
The steps involved in determining a Molecular Formula are: Find the mass of the empirical formula. Divide the molecular mass by the mass of the empirical formula. Multiply each subscript in the empirical formula by the answer.
Explanation:
Every orbital in a sub level is singly occupied before any orbital is doubly occupied is the statement of
Answer:
Hund's rule of maximum multiplicity
The point where ground water reaches the surface and pours out is called a summer? true or false
Answer:
False
Explanation:
Groundwater and surface water have a relationship.
Groundwater is the water that is contained in a subsurface layer of an underlying soil/rock whereas surface water is that found in a lake, river or some other surface cavities.
However, when groundwater is discharged to surface water bodies, it is said to be surface water. Thus the statement asked is false.
Is nitric acid a strong or weak acid. Explain your answer.
Answer:
Examples of strong acids are hydrochloric acid (HCl), perchloric acid (HClO4), nitric acid (HNO3) and sulfuric acid (H2SO4). A weak acid is only partially dissociated, with both the undissociated acid and its dissociation products being present, in solution, in equilibrium with each other.
Explanation:
Hope this helps you
escape room ocean and air currents. Escape room
Answer:
1683
Explanation:
i did that game a few weeks ago preeeettyyyyyyyy sure that's the right number
19. 1 mole = _____________________ _________________ g
Answer:
344.1g
Explanation:
Am I correct?
As gravity/distance increases between two objects, the gravitational pull between them weakens/strengthens
Yes, As the gravity/distance increases between two objects, the gravitational pull between them weakens/strengthens.
Explanation:There is a gravitational force of attraction between every object in the universe. The size of the gravitational force is proportional to the masses of the objects and weakens as the distance between them increases.
This is the chemical formula for Chormium (III) nitrate Cr(NO3)3Calculate the mass percent of nitrogen in chromium(III) nitrate.
Answer:
The percent composition for nitrogen in chromium(III) nitrate is 6%.
Explanation:
The mass percent of nitrogen in chromium(III) nitrate is 17.655%.
Calculation,
Molar mass of one oxygen = 16 g
molar mass of nine oxygen = 9 × 16 g = 144 g
molar mass of one nitrogen atom = 14 g
molar mass of three nitrogen atom = 3 × 14 g = 42 g
molar mass of one chromium atom = 51.99 g
molar mass of chromium (III) nitrate molecule = 144 g + 42 g + 51.99 g = 237.99 g
Mass percent of nitrogen = mass of three nitrogen atom× 100 /mass of chromium(III)nitrate
Mass percent of nitrogen = 42 g/237.99 g × 100 = 17.655%
What is mass percentage?The percentage of the mass of the element or solute divided by the mass of the compound or solute is called mass percentage
learn about mass percentage,
https://brainly.com/question/16885872
#SPJ2
What are two ways to determine the salinity level?
Answer: chlorinity titration and conductometry
Explanation:
Both magnetic fields and electric fields can exert a force true or false?
Answer:
false
Explanation:
An electric field may do work on a charged particle, while a magnetic field does no work.
Plz help it over science stuff
The element sulfur (S) is most likely to form covalent bonds with the element
helium (He).
magnesium (Mg).
zinc (Zn).
oxygen (O).
The element sulfur (S) is most likely to form covalent bonds with the element oxygen. Thus, the correct option for this question is D.
What do you mean by Covalent bonds?Covalent bonds may be defined as a type of chemical bond that significantly involves the mutual sharing of electrons in order to form electron pairs between atoms. This pairing of electrons is simultaneously attracted by the two atomic nuclei.
Sulfur is categorized into the category of nonmetal in group 6A, and therefore it has 6 valence electrons. In order to obey the octet rule, it needs to gain 2 electrons. It can do this by forming 2 single covalent bonds.
The sulfur atom subsequently shares four valence electrons with two oxygen atoms as two covalent double bonds, and shares its remaining two electrons with two oxygen atoms, forming two covalent single bonds.
Therefore, the element sulfur (S) is most likely to form covalent bonds with the element oxygen. Thus, the correct option for this question is D.
To learn more about Covalent bonds, refer to the link:
https://brainly.com/question/3447218
#SPJ6
A gas sample is found to contain 39.10% carbon, 7.67% hydrogen, 26.11% oxygen, 16.82% phosphorus, and 10.30% fluorine. If the molecular mass is 184.1 g/mol, what is the molecular formula?
Answer:
C6H14O3F
Explanation:
The first step is to divide each compound by its molecular weight
Carbon
= 39.10/12
= 3.258
Hydrogen
= 7.67/1
= 7.67
Oxygen
= 26.11/16
= 1.63
Phosphorous
= 16.82/31
= 0.542
Flourine
= 10.30/19
= 0.542
The next step is to divide by the lowes value
3.258/0.542
= 6 mol of C
7.67/0.542
= 14 mol of H
1.63/0.542
= 3 mol of O
0.542/0.542
= 1 mol of P
0.542/0.542
= 1 mol of F
Hence the molecular formula is C6H14O3F
What is the density of nitrogen gas at 356.4 K?
Answer:
Nitrogen gas (chemical symbol N) is generally inert, nonmetallic, colorless, odorless and tasteless. Its atomic number is 7, and it has an atomic weight of 14.0067. Nitrogen has a density of 1.251 grams/liter at 0 C and a specific gravity of 0.96737, making it slightly lighter than air.
Explanation:
:)
A sample of NH3(g) is placed in a rigid container. When the equilibrium below is established, the partial pressure of hydrogen gas is 0.978 atm. What is the partial pressure of N2(g) at equilibrium?
Answer:
PpN₂ = 0.326 atm
Explanation:
In this case, let's write the equilibrium reaction taking place here:
2NH₃(g) <------> 3H₂(g) + N₂(g)
Now, we know that when the reaction reach the equilibrium the partial pressure of H₂ is 0.978 atm, so, let's write an ICE chart and see what's happening here:
2NH₃(g) <------> 3H₂(g) + N₂(g)
i) y 0 0
c) -2x +3x x
e) y-2x 3x x
At the beggining we just have the sample of NH₃, we don't know how much but we don't need that data to get the partial pressure. In equilibrium, its produced hydrogen and nitrogen, and we know how much of hydrogen was produced, so, with that we can solve for the value of the partial pressure of NO by a simple math operation:
PpH₂ = 0.978 atm = 3x
PpN₂ = x
PpN₂ = PpH₂ / 3
PpN₂ = 0.978 / 3
PpN₂ = 0.326 atmHope this helps
Measurements show that the enthalpy of a mixture of gaseous reactants increases by 319kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that 92kJ of work is done on the mixture during the reaction. Calculate the change of energy of the gas mixture during the reaction in kJ.
Answer:
the change in energy of the gas mixture during the reaction is 227Kj
Explanation:
THIS IS THE COMPLETE QUESTION BELOW
Measurements show that the enthalpy of a mixture of gaseous reactants increases by 319kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that -92kJ of work is done on the mixture during the reaction. Calculate the change of energy of the gas mixture during the reaction in kJ.
From thermodynamics
ΔE= q + w
Where w= workdone on the system or by the system
q= heat added or remove
ΔE= change in the internal energy
q=+ 319kJ ( absorbed heat is + ve
w= -92kJ
If we substitute the given values,
ΔE= 319 + (-92)= 227 Kj
With the increase in enthalpy and there is absorbed heat, hence the reaction is an endothermic reaction.
Number of atoms in 2.56 moles of He
1.54 × 10²⁴ atoms He
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
MolesAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
[Given] 2.56 moles He
[Solve] atoms He
Step 2: Identify Conversion
Avogadro's Number
Step 3: Convert
[DA] Set up: [tex]\displaystyle 2.56 \ mol \ He(\frac{6.022 \cdot 10^{23} \ atoms \ He}{1 \ mol \ He})[/tex][DA] Multiply/Divide [Cancel out units]: [tex]\displaystyle 1.54163 \cdot 10^{24} \ atoms \ He[/tex]Step 4: Check
Follow sig fig rules and round. We are given 3 sig figs.
1.54163 × 10²⁴ atoms He ≈ 1.54 × 10²⁴ atoms He
PLEASE PLEASE PLEASEEE HELP!!
DUE IN 10 MINUTES!!
DIMENSIONAL ANALYSIS CHEMISTRY SUPER easy MOLE CONVERSIONS!!
Question : How many moles of O2 are in the sample of 3.6 kilograms of air if 21% of the air is oxygen O2 by mass?
Answer:
47.25 moles
Explanation:
First we find the amount of O2 in mass in air
That will be = (21/100) x 3.6
This will give us=0.756 kg
Now we want to find the moles, so we convert this mass into grams since we are going to be working with grams= 0.756 x 1000 = 756 grams
Now, to find the number of moles:
moles= mass / molar mass
in this case mass is 756 grams and molar mass of oxygen is 16
So, the mass divided by molar mass would be =756/16= 47.25 moles of O2