Answer:
C
Explanation:
(A+B) are compounds and D is mixtures
Which of the following is an example of a pure substance?
A. beer
C. halo-halo
B. ethyl alcohol
D. silver spoon
Calculate the number of molecules in 2.00 moles H2S.
Express your answer numerically in molecules.
Answer:
The answer is
1.204 × 10²⁴ moleculesExplanation:
The number of molecules can be found by using the formula
N = n × Lwhere n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question we have
N = 2 × 6.02 × 10²³
We have the final answer as
1.204 × 10²⁴ moleculesHope this helps you
A black bear can run 35.0 mph how long will it take to run 1.95 x 10^4?
A. 129
B. 0.360
C. None of the above
D. 0.106
E. 13
Answer:
The correct answer is C. None of the above.
Explanation:
To determine how long the black bear will run, the distance it will travel must first be determined. Thus, the proposed calculation must be solved.
1.95 x 10 ^ 4
1.95 x 10 x 10 x 10 x 10
19.5 x 10 x 10 x 10
195 x 10 x 10
1950 x 10
19500
Thus, the bear will run 19,500 miles, so, running at 35 mph, it will take about 557 hours to run that distance (19,500 / 35).
A sample of an ideal gas has a volume of 2.38 L at 283 K and 1.03 atm. Calculate the pressure when the volume is 1.97 L and the temperature is 307 K.
Gas Has A Volume Of 2.21 L At 287 K And 1.11 Atm. Calculate The Pressure When The Volume Is 1.03 L And The Temperature
Explanation:
Predict: Note the type of reaction you expect for the reactants Kl and Pb(NO3)2
Answer:
double replacement
Explanation:
just did it
Answer:
Double replacement
Explanation:
Weather is not the same as climate. Which claim
identifies the main difference between these two concepts?
A. The main difference is how both are measured
B. Only weather includes information about the
temperature
C. Only climate includes information about
precipitation
O D. The main difference is the length of time over
which both are measured
Answer:
b. only weather includes information about the temperature
What is the correct order of star colors from hottest to coolest?
white, yellow, red, blue
yellow, orange, white, red
red, orange, yellow, blue-white
blue, white, yellow-white, orange
Answer: The answer is blue, white, yellow-white, orange.
Explanation: These are the two basic reasons for different star colors:
Temperature – cooler stars are red, warmer ones are orange through yellow and white. The hottest stars shine with blue light
Age – As a star ages it produces different chemicals which burn at different temperatures. We can use a star’s color to show its relative age
Answer:
OR D
Explanation:
D on edge 2020
What else heats the Earth when Permafrost melts?
Answer:
As those microbes thrive, they will release large amounts of methane, another climate-warming greenhouse gas. ... By the year 2100, they estimated, thawing permafrost could release enough carbon dioxide and methane to raise the average global temperature by 0.13 to 0.27 degree C (0.23 to 0.49 degree F). pls mark me brainlest :(
Explanation:
What is the total pressure of a container in kpa if the partial pressures are 1.25 atm and 66.7 psi?
Answer:
586 kpa(kilopascal/1000 pascals)
Explanation:
given 1.24 atm(standard atmosphere), and 66.7 psi(pound force per square inch).
To find the total pressure we should use dalton's law of partial pressures which is the sum of the pressures of each individual gas.
then we convert them to pascals and divide by 1000 to get the measurement in kilopascal.
knowing that 1 atmosphere is proportional to around 14.696 psi. We can multiply our given measure of atm by that and sum it by psi like so. 1.24×14.6959 = 18.22298.
Then,
18.22298+ 66.7 = 84.92298
psi.
Since 1 psi is proportional to around 6894.76 pascals. 1 psi will be 68.9476 kilopascal. 84.92298 * 6.89476 = 585.523336 ≈ 586
Which element is a gas?
A.Br
B.C
C.B
D.Be
Answer:
A.Br
Explanation:
Bromine is the only gas from the choices provided. It belongs to the group of halogens, group 7.
It has atomic number of 35 and it belongs to the p-block on the periodic table.
C is carbon and carbon is a solid matter B is boron and boron is a metalloid Be is beryllium and silvery white metalOnly Bromine is the gas from the given choices. It is fuming liquid and when exposed, it becomes gaseous.
Explain how scientists know the composition of the bottom layer of the cust?
What molar concentration of hydrochloric acid (HCl) is needed to prepare a disinfectant solution with a pH
Answer:
The correct approach is "3.1×10⁻³ M".
Explanation:
As we know,
[tex]pH=-log[H_{3}O^+][/tex]
[tex]pH=2.5[/tex]
[tex][H_{3}O]^+= \ ?[/tex]
Now,
⇒ [tex]-log[H_{3}O]^+=2.5[/tex]
⇒ [tex][H_{3}O]^+=10^{-2.5}[/tex]
⇒ [tex]=3.1\times 10^{-3} \ M[/tex]
So that the needed molar concentration of HCL will be:
= [tex]3.1\times 10^{-3} \ M[/tex]
A chemist working as a safety inspector finds an unmarked bottle in a lab cabinet. A note on the door of the cabinet says the cabinet is used to store bottles of pentane, tetrahydrofuran, carbon tetrachloride, methyl acetate, and ethanolamine. The chemist plans to try to identify the unknown liquid by measuring the density and comparing to known densities. First, from his collection of Material Safety Data Sheets (MSDS), the chemist finds the following information: liquid density pentane tetrahydrofuran carbon tetrachloride methyl acetate ethanolamine Next, the chemist measures the volume of the unknown liquid as and the mass of the unknown liquid as . Calculate the density of the liquid. Round your answer to significant digits. Given the data above, is it possible to identify the liquid
Answer:
The liquid can be identified
Explanation:
Given that density is defined as mass per unit volume.
We have the following information regarding the unknown liquid;
Mass= 1.40 kg = 1400 g
Volume = 1378 cm^3 = 1378 ml
Density of unknown liquid = 1400/1378 = 1.012 g/ml this is approximately 1.0 g/ml
It is possible to identify the liquid, the liquid is ethanolamine
why some metals are more dense than others
What type of bond is present between two atoms of zinc in a nickel
Answer:
Pure covalent
Explanation:
To know the type of bond between two atoms you must find the electronegativity difference of them:
If electronegativity difference is:
< 0.4: Pure covalent.
Between 0.4 and 1.8: Polar covalent.
> 1.8: Ionic.
The electronegativity of Zn is 1.65 and Ni is 1.91. Electronegativity difference is:
1.91 - 1.65 = 0.26
That means the type of bond is:
Pure covalentA deck of cards has dimensions 8.9cm x 5.72cm x 1.82 cm. What is the volume of the deck in cubic centimeters?
Answer:
92.65256 cm^3
Explanation:
To find this, we can simply multiply all three dimensions to get the answer in cubic centimeters, and we get the answer above. If you want to be more specific, we can go by the sigfig rule and the answer would be rounded to 93 cm^3.
How many protons, neutrons, and electrons are in C -14
A hawk swoops down and catches a squirrel. The squirrel provides energy for the hawk. What happens to the rest of the matter?
Answer:
The rest of the food molecule is converted to other carbon molecules. The hawk cannot consume all the parts of the squirrel. It will feed as a carnivore on the fleshy part of its prey. The matter is converted to other carbon molecules
Explanation:
3. Using the periodic table,
What is the average atomic mass of bromine?
What is the average atomic mass of magnesium?
How do your calculated answers in #1 and #2 compare to those on the periodic table?
Answer:
79.904 u for bromine
24.305 u
Not really sure what the 3rd question is asking
Explanation:
Scientists utilize models for a variety of different purposes, but each type of scientific model has limitations. What might
be a limitation of existing solar system models?
a. They are not based on experimentation.
b. They are used for prediction.
C. They cannot be changed.
d. They are based on current knowledge,
Please select the best answer from the choices provided
А
B
С
D
Answer:
D.They are based on current knowledge.
Explanation:
Guy above me is wrong
An antacid tablet contains 640.0 mg of magnesium oxide per tablet.
What volume of 0.1000 M stomach acid (HCI) could one tablet neutralize?
Answer:
317.6 mL
Explanation:
Step 1: Write the balanced neutralization equation
MgO + 2 HCl ⇒ MgCl₂ + H₂O
Step 2: Calculate the mass corresponding to 640.0 mg of MgO
The molar mass of MgO is 40.30 g/mol. The moles corresponding to 640.0 mg (0.6400 g) of MgO are:
0.6400 g × (1 mol/40.30 g) = 0.01588 mol
Step 3: Calculate the moles of HCl that react with 0.01588 moles of MgO
The molar ratio of MgO to HCl is 1:2. The moles of HCl are 2/1 × 0.01588 mol = 0.03176 mol
Step 4: Calculate the volume of 0.1000 M HCl that contains 0.03176 moles
0.03176 mol × (1 L/0.1000 mol) = 0.3176 L = 317.6 mL
How much space does 2 x 1022 atoms of copper take up?
How much space do 2 x 1022 copper pennies take up, using examples from the animation?
Answer:
2044
Explanation:
100 POINTS HELP!!!!!!!!!!!!!!!!!!!!
Given that,
Mass number of Ge = 70
Then,
Atomic number of Ge = 32
No. of protons = 32
No. of electrons = 32
No. of neutrons,
→ 70 - 32 = 30
Answer:
30 is correct
Explanation:
70 - 32 = 30 mark as brainliest
What is the density of a substance with a mass of 15.0 g and a volume of 5.0 mL?
A. 0.33 g/mL
B. 3.0 g/mL
C. 10.0 g/mL
D. 20.0 g/mL
Answer:
B. 3.0 g/ml
Explanation:
density formula: mass/volume
15/5=3
Which of the following is an example of work: bowling or reading? How do you know?
Which sample matter is a pure substance
Answer:
Explanation:
If you have options, could you please tell me so I can further help you. If you just need an example then
Examples of pure substances include iron, steel, and water
Hope this helps (:
Answer
These are the following answers
A) zinc oxide
B) sugar dissolved in water
C) pond water
D) soil
Explanation:
Order: Vitamin K (Aquamephyton) 1 mg IM x 1 dose Newborn: Weight 4 kg Supply: 10mg/mL vial How many mLs would be given
Answer:
Volume(ml) of drug required = 0.1 ml
So, medicine is safe for this child.
Explanation:
Given:
Desired dose (D)= 1 mg
Dose in hand (H) = 10 mg
Quantity (Q) = 1 ml
Computation:
Volume(ml) of drug = [Desired medicine / medicine in hand] Quantity.
Volume(ml) of drug required = [1/10]1
Volume(ml) of drug required = 0.1 ml
So, medicine is safe for this child.
The chemical formula for calcium chloride is
Answer: anhydrous CaCl 2 :0H 2 O
monohydrate CaCl 2 :1H 2 O
a di-hydrate CaCl 2 :2H 2 O
Explanation:
how many orbitals are in 6s sublevel
The azimuthal quantum number and magnetic quantum number corresponds to the s orbital is zero. Hence, there is only one m value and thus contains one orbital only.
What are quantum numbers ?The quantum numbers are numbers used to describe the position of an electron within an orbital. The principal quantum number n indicates the main energy level. The azimuthal quantum number l indicates the shape and type of orbital which have values from 0 to n-1.
The magnetic quantum number m indicates the number of orbitals for a sublevel. m can have values from + l to -l. The fourth quantum number s is called spin quantum number. For an electron the spin quantum number can be +1/2 or -1/2.
The n value for the 6s sublevel is 6. The azimuthal quantum number , l for an s orbital is zero. So its m quantum number has only one value that is zero. Hence, there is only one orbital in 6s sublevel.
Find more on quantum numbers:
https://brainly.com/question/16979660
#SPJ2
The phase of matter most likely to be present at absolute zero would be:
A)
plasma
B)
gas
C)
liquid
D)
solid
Answer:
D solid
Explanation: