Answer:
A dichotomous key is a tool that allows the user to determine the identity of items and organisms in the natural world. ... In each step, the user is presented with two statements based on characteristics of the organism. If the user makes the correct choice every time, the name of the organism will be revealed at the end
Explanation:
8. How much heat is released when 85.0 g of steam condense to liquid water?
Answer:
199920J
Explanation:
Given parameters:
Mass of steam = 85g
Unknown:
Heat released when the liquid is condensed = ?
Solution:
The heat released by the substance is given as;
H = mL
H is the heat released
m is the mass
L is the latent heat of steam = 2352J/g
Heat released = 85 x 2352 = 199920J
How many grams of chromium(II) sulfate, , must be dissolved to prepare 500. mL of a 0.219 M aqueous solution of the salt?
Which is a valid velocity reading for an object? 45 m/s 45 m/s north 0 m/s south 0 m/s
Answer:
45 m/s north
Explanation:
Edge 2020
Answer: (B) 45 m/s north
Explanation: right on edge 2020 (so basically the same reason as person above)
How many moles are in 8.30 X 10 to the power of 23, molecules of CO2?
Answer:
1.38 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where 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
[tex]n = \frac{8.30 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{8.3}{6.02} \\ = 1.3787...[/tex]
We have the final answer as
1.38 molesHope this helps you
At which temperature could air hold the most water vapor?
Answer:
Now, what happens if we turn the room thermostat up to 80 degrees F? Looking at your Capacity of Saturated Air table, you can see that as air temperatures rise, there is an increase in the ability of the air to hold moisture. At 80 degrees F the capacity of air increases to where it can hold 21.537 g/kg of water vapor.
Explanation:
Answer: At 80 degrees F the capacity of air increases to where it can hold 21.537 g/kg of water vapor.
Explanation:
Please help me with this
Answer:
b
Explanation:
Electrons have negative charges and Protons have positive.
you can remember this by (Pro)ton = (Pos)itive
Explain what is cellular growth and repair? Why is it important?
Answer:
Cell growth usually refers to cell proliferation, the increase in cell numbers that occurs through repeated cell division. Cell growth can also refer to the enlargement of cell volume, which can take place in the absence of cell division. As living things grow, some cells die or become damaged and need replacements. Some single-celled organisms use a type of mitosis as their only form of reproduction. In multicellular organisms, cell division allows individuals to grow and change by expanding the number of total cells.
Hope this helps!!!
A sample of He collected over water at a temperature of 20C has a pressure of 705 torr. What is the pressure of the dry gas? The vapor pressure of water at 20 degrees * C is 17.5 torr.
The pressure of the dry gas : 687.5 torr
Further explanationDalton's law of partial pressures states that the total pressure of a mixture of gases is equal to the sum of the partial pressures of the component gases
Can be formulated:
P tot = P1 + P2 + P3 ....
The partial pressure is the pressure of each gas in a mixture
Since the gas mixture consists of He and H₂O :
P tot=P He + P H₂O
[tex]\tt 705=P~He+17.5\\\\P~He=705-17.5=687.5~torr[/tex]
4. An atom is neutral because it has the same number of protons as it has:
electrons
O neutrons
O Neither... An atom isn't neutral!
Taking into account the constitution of an atom, an atom is neutral because it has the same number of protons as it has electrons.
Constitution of an atomAn atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element.
Every atom consists of a nucleus in which neutrons and protons meet and energy levels where electrons are located.
The neutron is an electrically neutral subatomic particle, while the proton has a positive electrical charge. Electrons have a negative charge, move around the nucleus at different energy levels and are attracted to protons, positive in the atom through electromagnetic force.
Atom electrically neutralAn atom is considered electrically neutral when it has the same number of positive and negative charges. That is, an electrically neutral atom has the same number of protons (with a positive charge) and electrons (with a negative charge).
In summary, an atom is neutral because it has the same number of protons as it has electrons.
Learn more about atom electrically neutral:
brainly.com/question/1814899
brainly.com/question/2449569
#SPJ2
For all six solutions tested during this experiment,
the
is always the same. That
means that it is a constant throughout the
experiment
You can infer from this experiment that the
difference in the solutions is due to the
which will cause different flame
colors.
Answer:
1. Chloride ion
2. Metal ion
3. The same as a sample with the identical metal ion.
Explanation: I Just took the quiz on Edge 2021
20 POINTS HURRY!!!
A relationship in which one species benefits and the other is harmed is
A. mutualism.
B. cooperation.
C. commensalism.
D. parasitism.
Answer:
C. commensalism.
Explanation:
Here is the answer
Answer: THE ANSWER IS A
Explanation:
The pH of a solution of 3-hydroxypropanoic acid is measured to be . Calculate the acid dissociation constant of 3-hydroxypropanoic acid. Be sure your answer has the correct number of significant digits.
Answer:
3.1 × 10⁻⁵
Explanation:
The pH of a 0.53 M solution of 3-hydroxypropanoic acid (HC₃H₅O₃) is measured to be 2.39. Calculate the acid dissociation constant of 3-hydroxypropanoic acid. Be sure your answer has the correct number of significant digits.
Step 1: Given data
Concentration of 3-hydroxypropanoic acid (Ca): 0.53 MpH of the solution: 2.39Step 2: Write the acid dissociation reaction
3-hydroxypropanoic acid is a weak acid that dissociates according to the following equation.
HC₃H₅O₃(aq) ⇄ C₃H₅O₃⁻(aq) + H⁺(aq)
Step 3: Calculate the concentration of H⁺
We will use the definition of pH.
pH = -log [H⁺]
[H⁺] = antilog -pH = antilog -2.39 = 4.07 × 10⁻³ M
Step 4: Calculate the acid dissociation constant (Ka) of 3-hydroxypropanoic acid
We will use the following expression.
Ka = [H⁺]² / Ca
Ka = (4.07 × 10⁻³)² / 0.53
Ka = 3.1 × 10⁻⁵
Please solve quickly!!!
Answer:
18 oxygen atoms
Explanation:
in order to from the 6 molecules carbon dioxide and 6 molecules of water you will have a total of 18 oxygen atoms
As a mixed two substance in a test tube she noticed that the test tube because warm she also noticed gas coming from the test tube based on mias observation what was most likely occurring inside the test tube
Answer:
A new substance was forming
Explanation:
suppose you wanted to make 100 grams of water what is the molar mass of water
3. Carbon -14 underwent radioactive decay and emitted beta particles.
a. Write an equation to represent this process
?
The decay reaction of Carbon-14 which releases Beta particles, resulting in the element Nitrogen-14
Further explanationRadioactivity is the process of unstable isotopes to stable isotopes by decay, by emitting certain particles,
alpha α particles ₂He⁴ beta β ₋₁e⁰ particles gamma particles ₀γ⁰ positron particles ₁e⁰ neutron ₀n¹Carbon-14 emits beta β ₋₁e⁰ particles , so the atomic number increases by 1, the mass number remains the same
Reaction
[tex]\tt \large{\boxed{\bold{_6^{14}C\rightarrow _7^{14}N+_{-1}^0e}}[/tex]
What do you think it is?
Which is an example of the electromagnetic force?
- A compass needle points north toward earths magnetic pole
- An iron nail rolls off a table and falls to the ground
- the moon pulls on the water in earths oceans, causing tides
- protons that make up a nitrogen atom stays together in the nucleus
Answer:
The correct Answer is A.
proof below <3
This is how osmium appears in the periodic table.A purple box has O s at the center and 76 above. Below it says osmium and below that 190.23.
Rounded to the nearest whole number, how many neutrons, on average, are in an atom of osmium?
76
114
190
266
Answer:
it B 114 on edge 2020
Explanation:
UwU
Answer:
it B 114
Explanation:
Is ice a food or a drink
Answer:
a drink my guy
Explanation:
just frozen
It is a vocal music of Mindoro
Answer:
instrumental music is used in festivals, rituals, etc.
Explanation:
20 mL of 0.25 M of NH 3 is titrated with 0.40 M HCl. Calculate the pH of the solution after 20 mL HCl is added. Kb (NH3) = 1.8 × 10 −5.
a. 12.50
b. 7.00
c. 4.74
d. 1.12
Answer:
the pH of the solution after 20 mL HCl was added is 1.12
Option d) 1.12 is the correct answer
Explanation:
Firstly; number of mmols of NH₃ before addition of HCl = M x V = 0.25 x 20 = 5
Also number of mmols pf HCl added = M x V = 0.40 x 20 = 8
Number of mmols of NH₄Cl formed
= number of mmols of NH3 before addition of HCl = 5
Number of mmoles of HCl remained = 8 – 5 = 3
Therefore Total volume of solution = 20 + 20 = 40 mL
Molarity of HCl = 3 / 40 = 0.075 M
Molarity of NH₄Cl = 5 / 40 = 0.125 M
Therefore
Ka x Kb = 10⁻¹⁴
Ka x 1.8 x 10⁻⁵ = 10⁻¹⁴
Ka (NH₄Cl) = 5.56 x 10⁻¹⁰
[H+] from HCl = 0.075 M
[H+] from NH₄Cl = (Ka x C)^1/2
= (5.56 x 10⁻¹⁰ x 0.125)^1/2 = 8.34 x 10⁻⁶
Hence, [H+] from NH₄Cl is negligible.
pH = -log 0.075
pH = 1.12
Therefore the pH of the solution after 20 mL HCl was added is 1.12
Option d) 1.12 is the correct answer
What does a weather map use to represent areas of high air pressure?
An "A"
An "H"
An "L"
A "P"
Answer:
H
Explanation:
Some acids can eat through or what type of metals
Answer:
mixture of hydrochloric and nitric acid can dissolve noble metals, such as gold and platinum.
Explanation:
What type of atoms form covalent bonds?
Answer: :)
Explanation:
In a covalent bond, the atoms bond by sharing electrons. Covalent bonds usually occur between nonmetals. For example, in water (H2O) each hydrogen (H) and oxygen (O) share a pair of electrons to make a molecule of two hydrogen atoms single bonded to a single oxygen atom
Answer:
In a covalent bond, the atoms bond by sharing electrons. Covalent bonds usually occur between nonmetals. For example, in water (H2O) each hydrogen (H) and oxygen (O) share a pair of electrons to make a molecule of two hydrogen atoms single bonded to a single oxygen atom.
Explanation:
which si unit would be most appropriate for describing the lengeth of the shoe?
A weight of 22.25g was obtained when 10-mL of water at 27C was pipet to empty Erlenmeyer flask. What is the volume delivered by the pipet?
Answer:
the volume delivered by the pipette = 22.32 mL
Explanation:
To calculate this, let us first note that the density of water relates it weight and its volume (density = mass ÷ volume), hence we are going to use density to determine the volume.
Density of water = mass/volume = 0.997 g/ mL
mass = 22.25g
Density = 0.997g/mL
volume = ?
[tex]density = \frac{mass}{volume}\\\therefore volume = \frac{mass}{density}\\volume = \frac{22.25}{0.997}\\volume = 22.32\ mL[/tex]
∴ the volume delivered by the pipette = 22.32 mL
Please note that this calculation is based on the fact that the weight of the empty flask has been determined and canceled out.
The attraction that nonpolar molecules have for each
other is primarily caused by the presence of
Answer:
Van der waals forces
Explanation:
I just know
Which orbitals cannot exist?
2p 3p 4d 3f 6s 2d
Mark all that are wrong.
Answer:
The orbitals 3f and 2d cannot exist.
Explanation:
Hello!
In this case, considering the attached picture in which you find each energy level with the corresponding number of subshells, it is possible to infer level one has s subshell only, level 2 s and p, level 3 has s, p and d and from level 4 to 7 have s, p, d f, therefore, the orbitals 3f and 2d cannot exist.
Best regards!
what type of reactions are the following? ( single displacement, double displacement, synthesis, or decomposition)
4Mn3O4(s) + O2(g) -> 6Mn2O3(s)
Al2O3(aq) + 3C(s) ->3CO(g) + 2Al(l)
Ba(C2H3O2)2(aq) + Na2CO3(aq) -> BaCO3(s) +2NaC2H3O2(aq)
KOH(aq)+HBr(aq) -> KBr(aq)+H2O(l)
Answer:
1. synthesis
2. single displacement
3.double displacement
4.double displacement
Explanation:
1. here Mangananes (iv) oxide further reacts with oxygen to form Manganese (iii) oxide , two reactants making one product .
2. Carbon replaces aluminium from aluminium oxide to make pure aluminium and carbon monoxide and carbon dioxide.
3. sodium replaces barium to make sodium acetate , barium replaces sodium to make barium carbonate ( precipitate )
4. potassium replaces Hydrogen to produce potassium bromide, while hydrogen and hydroxide ions combine to make water .
