Answer:
hydrogen oxygen or nitrogen
Explain how the hypothalamus and certain endocrine glands work together to maintain the following conditions in the body. Specify the endocrine glands involve and the hormones it releases.
Answer:
Nerve cells in the hypothalamus make chemicals that control the release of hormones secreted from the pituitary gland. The hypothalamus gathers information sensed by the brain (such as the surrounding temperature, light exposure, and feelings) and sends it to the pituitary.
Explanation:
The acidic ingredient in vinegar is acetic acid. The pH of vinegar is around 2.4, and the molar concentration of acetic acid in vinegar is around 0.85 M. Based on this information, determine the value of the acid ionization constant, Ka, for acetic acid.
Answer: The value of acid ionization constant [tex]K_a[/tex] for acetic acid is [tex]1.87\times 10^{-5}[/tex]
Explanation:
[tex]CH_3COOH\rightarrow H^+CH_3COO^-[/tex]
cM 0 0
[tex]c-c\alpha[/tex] [tex]c\alpha[/tex] [tex]c\alpha[/tex]
So dissociation constant will be:
[tex]K_a=\frac{(c\alpha)^{2}}{c-c\alpha}[/tex]
Give c= 0.85 M and [tex]pH[/tex] = 2.4
[tex]pH=-log[H^+][/tex]
[tex][H^=}=c\times \alpha=10^{-2.4}=3.98\times 10^{-3}[/tex]
[tex]K_a=?[/tex]
Putting in the values we get:
[tex]K_a=\frac{(3.98\times 10^{-3})^2}{(0.85-3.98\times 10^{-3})}=1.87\times 10^{-5}[/tex]
Thus the value of acid ionization constant [tex]K_a[/tex] for acetic acid is [tex]1.87\times 10^{-5}[/tex]
Calculate the amount of heat energy required to heat up 15.9 grams of ice from -4 °C to 14°C.
Answer:
581 Joules.
Explanation:
Using the formula;
Q = m × c × ∆T
Where;
Q = amount of heat absorbed (J)
m = mass of substance (g)
c = specific heat capacity (J/g°C)
∆T = change in temperature (°C)
According to the information provided in this question;
Q = ?
mass of ice = 15.9g
initial temperature = -4°C
final temperature = 14°C
Hence, ∆T = 14 - (-4) = 14 + 4 = 18°C
specific heat capacity (c) of ice in J/g°C = 2.03 J/g°C
Using Q = m × c × ∆T
Q = 15.9 × 2.03 × 18
Q = 32 × 18
Q = 581 Joules.
pls help!!!!
Predict the missing component
in the nuclear equation.
1331 → X + -e
A
B
с
131 Cs
131Xe
1311
55
54
53
Answer: b
Explanation:
its b
The missing component in the nuclear equation.1331 → X + -e will be 131Xe54. option B is correct.
What is nuclear reaction?The particles in the nucleus are changed, and one element is transformed into another element when particles in the nucleus are gained or lost.
Nuclear reactions are processes in which one or more nuclides are produced from the collisions between two atomic nuclei or one atomic nucleus and a subatomic particle.
This was the first observation of an induced nuclear reaction, that is, a reaction in which particles from one decay are used to transform another atomic nucleus.
The most notable man-controlled nuclear reaction is the fission reaction which occurs in nuclear reactors. A target nucleus are within the range of nuclear forces for the time allowing for a large number of interactions between nucleons.
therefore , option B is correct.
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Match the word to the definition
Question 1 options:
simple diffusion
osmosis
facilitated diffusion
1.
Molecules move from high to low concentration
2.
Molecules move from high to low concentration with a transport protein
3.
Diffusion of water through a selectively permeable membrane
8. Of what importance is a smoker to a person keeping bees?
Answer:
they help to calm the bees when the person keeping the bees inspects there hives.
2Al(S)+1.5O2(S)→Al2O3(s) H= -1676.0 KJ
2Fe + 1.5O2 (S) →Fe2O3(S)
Then the enthalpy change for the following equation is _______KJ
2Al + Fe2 O3(S) → 2Fe +Al2O3(s)
pls i dont have time
Answer:
[tex]∆H = - 1676.0 - 0 \\ = - 1676.0 \\ heat \: gained \: in \: reaction \: of \: iron \: and \: oxygen \: is \: zero \: because \: it \: is \: not \: given[/tex]
The compound calcium carbonate contains the calcium ion (Ca2+) and the polyatomic carbonate ion (CO32-). Explain why calcium carbonate is considered to be an ionic compound when it contains both ionic and covalent bonds.
Answer:
Because of the electronegativity difference C-O (covalent) and Ca-O (ionic) bonds have.
Explanation:
Hello there!
In this case, in order to understand the polarity of this compound, calcium carbonate, it firstly necessary that it is comes from the definition of electronegativity, as a property defining the capacity to attract electrons from another atom; thus, since the electronegativities of calcium, carbon an oxygen are 1.0, 2.55 and 3.44, it is possible to realize this compound has O-Ca and O-C bonds according to its Lewis dot structure. In such a way, we calculate the difference electronegativity for these two bonds:
[tex]\Delta E_{O-Ca}=3.44-1.0 = 2.44\\\\\Delta E_{O-C}=3.44-2.55=0.89[/tex]
Thus, since 2.44 accounts for an ionic bond and 0.89 for a covalent one, we bear out the given statement in the question.
8 billion molecules of O2 gas
How many molecules are in 25 grams of NH3
A Flame test is an example of chemistry property. What evidence can you use to back your statement up?
Which advantage do multicellular organisms have over unicellule organisms
Answer:
Multicellular organisms thus have the competitive advantages of an increase in size without its limitations. They can have longer lifespans as they can continue living when individual cells die. Multicellularity also permits increasing complexity by allowing differentiation of cell types within one organism.
I need this question ASAP please
Answer:
Heeeeeeeeeeeeeloooooooooo
Explanation:
In science lab, Ellie combined sugar and distilled water. Ellie made
A. a mixture, which must be separated by chemical processes.
B. a compound, which must be separated by chemical processes.
C. a mixture, which can be separated through physical processes.
D. a compound, which can be separated through physical processes.
Answer:
C
Explanation:
The horse achieved its highest status during the___________dynasty (618-906 CE), a time of unparalleled political, artist, and cultural greatness.
A. Qin
B. Han
C. Tang
D. Shang
b) How many moles of Na2O can be produced from 13.5 moles Na?
Answer: 6.75 moles of [tex]Na_2O[/tex] can be produced from 13.5 moles Na
Explanation:
The balanced chemical equation for formation of [tex]Na_2O[/tex] from Na is:
[tex]4Na+O_2\rightarrow 2Na_2O[/tex]
According to stoichiometry :
4 moles of Na give = 2 moles of [tex]Na_2O[/tex]
Thus 13.5 moles of [tex]Na[/tex] give =[tex]\frac{2}{4}\times 13.5=6.75moles[/tex] of [tex]Na_2O[/tex]
Thus 6.75 moles of [tex]Na_2O[/tex] can be produced from 13.5 moles Na
Are electron shells or orbitals actually inside the atom or are they outside of the structure of the atom?
Answer:
Electrons in atoms occupy energy levels, also called electron shells, outside the nucleus . Different shells can hold different maximum numbers of electrons. The electrons in an atom occupy the lowest available energy level first. This is the shell nearest the nucleus.
Explanation:
No link or Files plz i need help with this one i been stuck on it for a long time
Answer:
The particles in a solid are tightly packed and locked in place. Although we cannot see it or feel it, the particles are moving or vibrating in place.
Answer:
molecules in a solid are tightly packed together and vibrate about their fixed positions.
Explanation:
there is very little movement between molecules in a solid since there is not much space between the molecules, hence the slight vibrations.
i hope this helps! :D
What type of chemical replacement is RbNO3 + BeF2 →Be(NO3)2 + RbF
Answer:
Double replacement
Explanation:
Name the following carboxylic
acid:
COOH
A. 1-methylpentanoic acid
B. 2-methylpentanoic acid
C. 1-methylbutanoic acid
D. 5-ethylpentanoic acid
Answer:
methylpentanoic acid,,,,,I guess so
The following carboxylic acid is 2-methylpentanoic acid.
What is a carboxylic acid?A carboxylic acid is an organic compound that contains the carboxyl functional group. The general formula for a carboxylic acid can be abbreviated as R−COOH.
Pentanoic acid can be prepared by reacting a butyl halide with magnesium to obtain a Grignard reagent, which is further reacted with carbon dioxide to give valeric salt.
Hence, the following carboxylic acid is 2-methylpentanoic acid.
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B. Calculate the Pressure of 20.0 mole of helium in a 10.0 L cylinder at 273 K. [a = 0.0341 atm*L^2/mol^2 ; b = 0.0237L/mol ; R = 0.08205 L*atm/mol*K) *
87.3 atm
46.9 atm
55.5 atm
12 kPa
Answer:
46.9 atm
Explanation:
Applying Van der waals equation
P = [nRT/(V-nb)]- (an²/V²)............... Equation 1
Where P = pressure, T = temperature, n = number of moles, V = volume, R = Universal constant, a and b = gas constant
Given: n = 20 moles, R = 0.08205 L.atm/mol.K, T = 273 K, V = 10.0 L, a = 0.0341 atm.L²/mol², b = 0.0237L/mol
Substitute these values into equation 1
P = [(20×0.08205×273)/(10-20×0.0237)]-(0.0341×20²/10²)
P = (447.993/9.526)-0.1364
P = 47.028-0.1364
P = 46.9 atm
state the reason why the liebig condenser should be slanting and not horizontal?
Answer:
Explanation:I hope it help:)
Instead of being utilized horizontally, the Liebig condenser is frequently tilted because this promotes greater cooling and circulation of the cooling fluid.
What is Liebig condenser?A popular condenser used in chemistry to cool and condense heated vapor or gas into liquid form is the Liebig condenser.
It is constructed with an inner tube that allows hot vapor or gas to pass through and an outer jacket that allows cooling fluid, such water, to flow through in order to condense the vapor or gas.
Slanted condensers allow cooling liquid to pass through the outer jacket more freely, improving heat transfer and increasing cooling effectiveness.
Therefore, it provides for better cooling and circulation of the cooling fluid, the Liebig condenser is often utilized in a tilted position as opposed to a horizontal one.
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Can someone please explain what to do it’s late at night and I need sleep but I forgot I had this homework please help me with a few questions I’m desperate :(
Answer:
1) it takes 13 second
2) 2100 miles
3) 40 miles / hours
4) 730 meters
If 260 grams of KBR was dissolved in 200 grams of water at 100 degrees Celsius, the solution would be...
a.) saturated
b.) unsaturated
c.) supersaturated
d.) saturated with excess.
Answer:
d
Explanation:
because the water has to be more , the KBR Is (excess) but however it is saturated!
thank you
How many carbon atoms are in 1.25 mol of silver acetate?
The number of carbon atoms present in 1.25 mol of silver acetate is 1.875 × 10²³.
What is Avogadro's number?Avogadro's number is define as the number of atoms of any substance present in one mole of that substance, and it is equal to 6.022 × 10²³, i.e.
1 mole = 6.022 × 10²³ atoms/mol
Given moles of silver acetate = 1.25 moles
Number of atoms of silver acetate in 1.25 moles = 1.25 × 6.022 × 10²³ = 7.5×10²³
Molecular formula of silver acetate is CH₃CO₂Ag, means in this molecule total 8 atoms are present so number of carbon atom will be calculated as:
Carbon atoms = (2× 7.5 × 10²³) / 8 = 1.875 × 10²³ atoms [here we multiply by 2 because 2 atoms of carbon is present in olecule]
Hence required atoms of carbon is 1.875 × 10²³.
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What is the total pressure inside a flask that contains 2.15 atm helium, 4.62 atm xenon, and 0.65 atm argon?
Answer:
7.42 atm
Explanation:
The total pressure is just the sum of partial pressures:
2.15 + 4.62 + 0.65 = 7.42 atm
Scenario: You are testing two different household solutions with your cabbage indicator, using the color key to the right.
One solution turns blue. A possible hydrogen ion concentration for this solution is: D
1 × 10-2 M
5 × 10-2 M
5 × 10-4 M
1 × 10-8 M
Answer:
DDDDD
Explanation:
According to the indicator theory, the hydrogen ion concentration for this solution is 1 × 10⁻⁸ M.
What is an indicator?Indicator is defined as a chemical substance which is chemically a weak acid or a weak base which changes it's color depending upon the concentration of hydrogen ions present in the solution.They dissociate slightly in water to produce ions.
These are generally derived from plant pigments and are of slightly acidic or basic in nature.There are three types of indicators:
1) natural indicators
2) synthetic indicators
3) olfactory indicators.
These are mainly used in determination of end point of titrations. Every indicator has it's pH range in which it can perform effectively.These are usually organic compounds.
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A graduated cylinder was filled with 25.0 mL of water. A solid object was immersed in the cylinder, raising the water level to 32.9 mL. The volume of the object was calculated as 7.9 mL. The solid has a mass of 69.2 grams. What is the density of the object?
Answer:
Density of the object is 8759.494 grams/L
Explanation:
As we know density of an object is mass of the object divided by its volume
Given
Volume of the object is equal to the change in volume of water with in the cylinder when the object was immersed in water.
Hence, volume of object is equal to
[tex]32.9 -25 = 7.9[/tex] mL
Mass of the object is [tex]69.2[/tex] grams
Density
[tex]= \frac{69.2}{7.9 *10^{-3}}\\= 8759.494[/tex] grams/L
Density of the object is 8759.494 grams/L
Do the rocks get older or younger as you go away from the Mid Atlantic Ridge
towards the continents? Why? EXPLAIN.
Answer:
Rocks get older as we go away from the Mid Atlantic Ridge towards the continents
Explanation:
As the plates move away from each other, new ocean lithosphere is created at the ridge. This also widens the ocean basin and leads to sea floor spreading.
The rock of the ocean floor are symmetrically aligned and they get become older as they move away from the crest of the ridge.
Thus, rocks get older as we go away from the Mid Atlantic Ridge towards the continents
Four scientist collected data on the blood pressure of 30 people. Which scientist most likely had a problem with the experimental design?
Answer:
Scientist 3
Explanation: