Answer:
E = 2.85×10⁻¹⁹ J
Explanation:
Given data:
Wavelength of light = 700 nm
Frequency of light = 4.3×10¹⁴ s⁻¹
What is the energy of light = ?
Solution:
Formula:
E = h × f
h = plancks constant = 6.63×10⁻³⁴ Js
by putting values,
E = 6.63×10⁻³⁴ Js × 4.3×10¹⁴ s⁻¹
E = 28.5×10⁻²⁰ J
E = 2.85×10⁻¹⁹ J
Which is the correct electron configuration for the element nitrogen
Answer: 1s²2s²2p³ or it can also be 3s²2p³
2. Look at the chemical formula of a compound below. Use the periodic table to
answer the following question.
NH4
Which elements are found in this compound? (6.5A)
F. Nitrogen and Hydrogen
G. Nitrogen and Helium
H. Nickel and Hydrogen
J. Nickel and Helium
Which of the following greenhouse gasses does not contribute to climate change
The options are;
A) Carbon dioxide
B) Carbon Monoxide
C) Chloro fluoro carbon and methane
D) Refrigerant Freon
Answer:
B) Carbon Monoxide
Explanation:
Greenhouse gases are compounds available in the atmosphere which are capable of absorbing infrared radiation, thereby making heat in the atmosphere to be trapped and held there. The most common ones are carbon Monoxide, carbon dioxide, chloro-fluoro carbon, methane, nitrous oxide, ozone and freon. Out of them, the one that is the most dangerous and doesn't contribute to climate change is carbon monoxide because it is a silent killer gas
Thus, option B is correct
How many formula units are there in 50.3 moles potassium chloride?
3.03 × 10²⁵ formula units KCl
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Unit 0
Reading a Periodic TableWriting CompoundsAtomic Structure
Using Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:Step 1: Define
50.3 mol KCl (Potassium chloride)
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
[tex]\displaystyle 50.3 \ mol \ KCl(\frac{6.022 \cdot 10^{23} \ formula \ units \ KCl}{1 \ mol \ KCl} )[/tex] = 3.02907 × 10²⁵ formula units KCl
Step 4: Check
We are given 3 sig figs. Follow sig fig rules and round.
3.02907 × 10²⁵ formula units KCl ≈ 3.03 × 10²⁵ formula units KCl
what would happen to the volume of 10L carbon dioxide, if the pressure is doubled and temperature is constant?
Answer:
The volume will goes to decrease.
Explanation:
The given problem will be solved through the Boyle's law,
"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"
Mathematical expression:
P₁V₁ = P₂V₂
P₁ = Initial pressure
V₁ = initial volume
P₂ = final pressure
V₂ = final volume
when pressure is going to increase the volume will goes to decrease and vice versa.
Consider the initial volume is 10 L at initial pressure of 15 atm when pressure is increased to 30 atm the volume will be,
Now we will put the values in formula,
P₁V₁ = P₂V₂
15 atm × 10 L = 30 atm × V₂
V₂ = 150 atm. L/ 30 atm
V₂ = 5 L
Which of the following has no electrical charge?
Select one:
a. proton
b. neutron
c. electron
Answer:
neutron
Explanation
neutrons have no net charge
Which reproductive structure is correctly paired with its functions
Answer:
(4) sperm - transports genetic material
Explanation:
Which reproductive structure is correctly paired with its function'?
(1) uterus - usual site of fertilization
(2) testis - usual location for egg development
(3) ovary - delivers nutrients to the embryo
(4) sperm - transports genetic material
Solution:
The uterus (also known as the womb) is where the fertiled egg (foetus) stays until it is ready to be delivered. The usual site of fertilization is the fallopian tube.
The testis is responsible for the production of sperm and hormones. The uterus is where the egg development takes place.
The ovary is responsible for the production of egg and hormones. The embryo receives nutrient through the fetus.
The sperm transports genetic material to the ovum.
Answer:
4
Explanation:
because ovaries def do not deliver nutrients to the embryo thats the placenta and the testis are DEF not a site for egg development and the uterus is not where fertilization happens i believe its where the fetus is kept and therefore the only correct answer is 4 :)
What types of radiation cause the parent isotope to change into a different element?
Answer:
Beta decay is most common in elements with a high neutron to proton ratio. Gamma decay follows the form: In gamma emission, neither the atomic number or the mass number is changed. A high energy gamma ray is given off when the parent isotope falls into a lower energy state.
Explanation:
pls mark me as brainliest
Describe what is happening when an object is in equilibrium ?
Answer:
in terms of chemistry, the forward reaction balances the backward reaction :)
Explanation:
Molar mass for C 3 H 6 (O H)2
Answer:
The answer is 76.0944
Explanation:
I hope this helps!
The molar mass and molecular weight of C3H6(OH)2 is 76.0944.
What is the percent composition of Ca(C2H3O2)2?
Select one:
a) 25.3% Ca, 30.4% C, 3.8% H, 40.5% O
b) 40.4% Ca, 24.2% C, 3.1% H, 32.3% O
c) 6.67% Ca, 26.67% C, 40.0% H, 26.67% O
d) 12.5% Ca, 25% C, 37.5% H, 25% O
Answer:
A
Explanation:
RMM of ca(c2h302)2=158
%Ca= 40/158×100=25.3
%C=48/158×100=30.3
%H=6/158×100=3.7
%O=64/158×100=40.5
Answer:
a) 25.3% Ca, 30.4% C, 3.8% H, 40.5% O
Explanation:
Molar mass of Ca(C₂H₃O₂)₂ = 158.160 g/mol
percent composition:
Ca = (40 /158.160 ) × 100
Ca = 25.3%
C = (48 /158.160 ) × 100
C = 30.4%
H = (6 /158.160 ) × 100
H = 3.8%
O = (64 /158.160 ) × 100
O = 40.5%
40.5% + 3.8% + 30.4% + 25.3% = 100%
It means 1st option is correct.
Which describes a stationary reference point?
A. A slower moving truck from the point of view of a car passing it
B. A plan from the point of view a falling sky driver
C. A tree from the point of view of someone in a moving car
D. The sun from the point of view of someone sitting outside
Answer: C
Explanation:
“First, I would want to find the fire’s origin and look for signs of accelerant use. If I was able to locate the origin, I would do my best to preserve the area. If not, …” Your ‘timeline’ should be detailed but it does not need to be as extensive as a research paper or essay. You can format your timeline however you like – as an actual timeline, a bulleted list, or short paragraphs as long as you include a clear format like first, second, third, etc. Be sure to include at least six steps. You can create your ‘timeline’ in a word processing program or a slide presentation. You will be graded on the accuracy of your timeline as well as mechanics and grammar. For more details, see the rubric below
Answer:
1. First, I would observe the fire and the conditions of the scene, looking for the origin of the fire and looking in an accelerant was used. If I could find the origin of the fire I would make sure to not have any evidence damaged, and if I could not find the origin of would look from other forms of evidence, like clothing, flammable liquids, or igniters.
2. Secondly, I would make sure to preserve the area, and document the scene, with pictures and notes and any other forms of recording. It is important to initiate permanent documenting of the scene.
3. Thirdly, I would try to find anything flammable with a snider, and run the tests on what it could be. It is also important to make sure everybody is safe, and to evaluate for any safety hazards. Finally, I would create safety zones and communicate the hazards to people near the scene.
4. I would next contact the incident commander, and also search for any evidence that says whether the fire was an accident or was arson. If the fire was arson, I would locate any evidence that could lead to suspects, and if the fire was an accident, I would try to find all the evidence that shows how it happened.
5. Once I collect all the evidence, I would organize it in the best way possible and then I would use the hydrocarbon method in order to test the evidence that I found.
6. After the results come back based on the evidence, I would compare the results with the information found about the fire security in the building, the people involved, and I would start in trying to solve the crime.
what element is found on the left side of the periodic table
Answer:
Mostly Metals, But hydrogen is the only one that isn't.
two answer multiple choice-- please help!
Study the reaction.
NH4+ + NO2– ⟶ N2 + 2H2O
The rate of this reaction is proportional to the concentration of ammonium (NH4+) and the concentration of nitrogen dioxide (NO2–).
What is the rate law of this reaction?
Rate = K[NH4+][NO2–]
Rate = K[N2][H2O] ^2
Answer:
Rate = K[NH₄⁺][NO₂⁻]
Explanation:
In kinetics studies of reaction, rate law is a mathematical expression that relates speed of reaction with concentrations of the reactants. For a reaction:
aA + nN → cC + dD
The rate law is expressed in terms of [A] and [B] as follows:
Rate = K[A]ᵃ[N]ⁿ
Where K is rate constant.
For the reaction:
NH4+ + NO2– ⟶ N2 + 2H2O
The rate law is:
Rate = K[NH₄⁺][NO₂⁻]As was said in the problem, the rate is porportional to [NH₄⁺] and to [NO₂⁻]
When the equation H₂ + N₂ --->NH₃ is completely balanced using the smallest whole numbers, the sum of all the coefficients will be
Answer:
6
Explanation:
The equation given in this question is:
H₂ + N₂ ---> NH₃
To balance this equation i.e to make sure that the number of atoms on each side of the equation is the same, one would make use of coefficients.
The balanced equation is:
3H₂ + N₂ ---> 2NH₃
The coefficients are the number behind each element or molecule. According to this question, the sum of each coefficient is 3 + 1 + 2 = 6
The boiling point of chlorine (Cl2) is 171.6 K. Which of the
following best predicts the boiling point of iodine (12)?
Answer:
The boiling point of iodine is 363.7°F / 184.3°C
Find the volume in milliliters (ml) of 25gof benzene. The density of benzene is 0.8765 g/mL
Answer:
28.52 mLExplanation:
The volume of a substance when given the density and mass can be found by using the formula
[tex]volume = \frac{mass}{density} \\[/tex]
From the question we have
[tex]volume = \frac{25}{0.8765} \\ = 28.52253...[/tex]
We have the final answer as
28.52 mLHope this helps you
how does a window demonstrate transmittance of light
Answer:
The proportion of light transmitted by glazing is specified by the Visible Light Transmittance, which is recorded as either TVw (visible transmittance of the window) or VLT (visible light transmittance). These terms are interchangeable, but in Australia, the Window Energy Rating Scheme uses Tvw in its ratings.
While the VLT/Tvw rating varies between 0 and 1, most double glazed windows rate between 0.3 and 0.7 , which means that between 30% and 70% of the available light passes through the window. The illustration above shows you how the view changes, as the amount of light getting through the window changes.
Explanation:
HELP ASAP MY LESSON IS BEING TIMED!!!
1) Choose the correct answer.
_____ states when one object applies a force on a second object, the second object applies an equal force in the opposite direction.
Newton’s third law of motion
The law of conservation of momentum
The law of conservation of energy
2) Choose the correct answer.
The law of conservation of momentum states that the total movement of a group of objects stays the same unless acted on by _____ forces.
unbalanced
balanced
opposite
3) Choose the correct answer.
Forces work in pairs; the _____ force is the initial force applied to an object.
momentum
action
reaction
Answer:
1. Newton's third law of motion
2. Unbalanced
3. Action
Why is the C-O bond considered to be polar?
The molecule is symmetrical.
The electronegativity difference of the atoms in the bond.
Answer:
The electronegativity difference of the atoms in the bond.
Explanation:
Carbon is electropositive while Oxygen is highly electronegative, hence highly polar due to strong intermolecular forces.
The molecule is not symmetrical because it's dipole moments don't cancel out.
Diamond has a density of 3.26 g/cm^3. What is the mass of a diamond that has a volume of 25 cm^3?
Answer:
81.5 gExplanation:
The mass of a substance when given the density and volume can be found by using the formula
mass = Density × volume
From the question we have
mass = 25 × 3.26
We have the final answer as
81.5 gHope this helps you
A serving of Frosted Flakes cereal contains 235,000 J of energy. Calculate the change in temperature (ΔT) that would occur if this food was used to heat 1,000 grams of water.
Answer:
55.95K
Explanation:
its obtained from Q=MCT where
Q-amount of heat
M-mass of water
C-specefic heat capacity of water
T-change in temperature
How many molecules of oxygen are produced when a sample of 38.9 g of water is decomposed by electricity?
A) 6.5 x 10^23
B) 1.3 x 10^24
C) 2.6 x 10^24
D) 2.3 x 10^25
Answer:
A) [tex]6.5\times 10^{23}\ \text{molecules}[/tex]
Explanation:
m = Mass of water = 38.9
M = Molar mass of water = 18 g/mol
[tex]N_A[/tex] = Avogadro's number = [tex]6.022\times 10^{23}\ \text{mol}^{-1}[/tex]
The reaction of electrolysis would be
[tex]2H_2O(l)\rightarrow 2H_2(g)+O_2(g)[/tex]
Number of moles of [tex]H_2O[/tex]
[tex]n=\dfrac{m}{M}\\\Rightarrow n=\dfrac{38.9}{18}\ \text{mol}[/tex]
From the reaction it can be seen that 2 moles of [tex]H_2O[/tex] gives 1 mole of [tex]O_2[/tex]
So, number of moles of [tex]O_2[/tex] produced is
[tex]\dfrac{38.9}{18}\times \dfrac{1}{2}=1.081\ \text{mol}[/tex]
Number of molecules
[tex]1.081N_A=1.081\times 6.022\times 10^{23}\\ =6.5\times 10^{23}[/tex]
So, [tex]6.5\times 10^{23}\ \text{molecules}[/tex] of oxygen is produced.
A cook places a pan of food on a hot stove and leaves it there. When the food is just about done cooking, which of the following will most likely be true?
A.
The pan will be hotter than the stove.
B.
The pan will not have changed in temperature.
C.
The pan will be the same temperature as the stove.
D.
The pan will be cooler than the stove.
Answer:
C.
The pan will be the same temperature as the stove.
Explanation:
The atoms in NaOH are:
Sodium, oxygen, and hydrogen
Naquida, oxygen, and hydrogen
Naoline and Oxyhydrous
Nitrogen, Argon, Oxygen, and Hydrogen
Answer:
Sodium, Oxygen and Hydrogen
Explanation:
Na= Sodium
O= Oxygen
H= Hydrogen
What is the medium of the wave shown in the paragraph?
Answer:
The water is the medium of the wave
What is the evidence that Mars once had flowing liquid water? Why is this important?
Answer:
New findings from NASA's Mars Reconnaissance Orbiter (MRO) provide the strongest evidence yet that liquid water flows intermittently on present-day Mars. Using an imaging spectrometer on MRO, researchers detected signatures of hydrated minerals on slopes where mysterious streaks are seen on the Red Planet. These darkish streaks appear to ebb and flow over time. They darken and appear to flow down steep slopes during warm seasons, and then fade in cooler seasons. They appear in several locations on Mars when temperatures are above minus 10 degrees Fahrenheit (minus 23 Celsius), and disappear at colder times.
Explanation:
All living organisms are composed of
OA. at least three cells.
ОВ.
one or more cells.
OC. at least 100 cells.
OD. only one cell.
Answer:
B
Explanation:
all living things are composed of one or more cells
What is the correct name for H3AsO3
Answer:
arsenous acid
Explanation: