Answer:
The unit of energy you measure in is joule.
how are the messages of the endocrine system moved around the body?
Answer:
Endocrine glands make chemicals called hormones and pass them straight into the bloodstream. Hormones can be thought of as chemical messages. From the blood stream, the hormones communicate with the body by heading towards their target cell to bring about a particular change or effect to that cell.
what is the hydrogen ion concentration in a 0.10M solution of KOH?
KOH is a strong base, so [OH-] = 0.10 M = 1.0 x 10^-1 M
[H+][OH-] = Kw
Kw = 1.0 x 10^-14
[H+] = 1.0 x 10^-14 / 1.0 x 10^-1 = 1.0 x 10^-13 M
1.The water molecule is-
A. Slightly negative near the hydrogen atoms and slightly positive near the oxygen atom
B. Slightly positive in all areas of the molecule
C. Slightly negative near the oxygen atom and slightly positive near the hydrogen atoms
D. The same charge in all areas of the molecule
Answer:
C.
Explanation:
Slightly negative near the oxygen atom and slightly positive near the hydrogen atoms
A concept map is shown.
Which of the following topics best completes the graphic organizer?
A. Physical properties of elements
B. Chemical properties of elements
C. Evidence of a physical change
D. Evidence of a chemical change
Answer:
C Evidence of Physical change
Explanation:
Because Solid forms is a physical change and so are all the other ones
How many Hydrogen atoms are in the following compound (including the coefficient): 3(NH4)2CO3
Answer:
i believe it would be 12
Explanation:
because 3*4 is 12
Define pollination, fertilization and photosynthesis process
If the He H e injected into the abdomen produces a pressure of 22 mmHg m m H g and a volume of 2.7 L L at 31 ∘C ∘ C , how many grams of He H e were used?
Answer:
1280.27 g
Explanation:
Pressure = 22 mmHg / 760 = 0.0289 atm (Converting to atm by dividing by 760)
Volume = 2.7 L
Temperature = 31 ∘C + 273 = 304 K
Mass = ?
Using the ideal gas equation;
PV = nRT
n = RT / PV = 0.0821 * 304 / ( 0.0289 * 2.7)
n = 319.86 mol
Mass = Number of moles * Molar mass
Mass = 319.86 * 4.002602
Mass = 1280.27 g
whats the salt produced when sulfuric acid reacts with iron?
Answer:
Dilute sulfuric acid reacts with metals higher than hydrogen in the reactivity series to form sulfate salts and hydrogen gas. Note the metal reactions are different with concentrated sulfuric acid. Iron is cleaned free from rust prior to coating with tin to form tinplate and with zinc to form galvanized iron.
Which term refers to an electrochemical cell that uses a spontaneous redox reaction to produce an electric current?
electrolyte
voltaic cell
electrolytic cell
cathode
is an example of a solution that contains a dissolved substance
Answer:
An aqueous solution is water that contains one or more dissolved substances. The dissolved substances in an aqueous solution may be solids, gases, or other liquids.
If the football indoors had a volume of 5.33 L at 21degrees celsuis, what is the volume of the football outside where the temp is 10C (temp must be in K) MUST SHOW WORK
Answer:
5.13 L
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 5.33 L
Initial temperature (T₁) = 21 °C
Final temperature (T₂) = 10 °C
Final volume (V₂) =?
Next, we shall convert celsius temperature to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
Initial temperature (T₁) = 21 °C
Initial temperature (T₁) = 21 °C + 273
Initial temperature (T₁) = 294 K
Final temperature (T₂) = 10 °C
Final temperature (T₂) = 10 °C + 273
Final temperature (T₂) = 283 K
Finally, we shall determine the final volume. This can be obtained as follow:
Initial volume (V₁) = 5.33 L
Initial temperature (T₁) = 294 K
Final temperature (T₂) = 283 K
Final volume (V₂) =?
V₁/T₁ = V₂/T₂
5.33 / 294 = V₂ / 283
Cross multiply
294 × V₂ = 5.33 × 283
294 × V₂ = 1508.39
Divide both side by 294
V₂ = 1508.39 / 294
V₂ = 5.13 L
Thus, the new volume of the football is 5.13 L
How many grams of Fe2O3 are needed to produce 51.9 g of CaO?
Answer:
98.8g (3 s.f.)
Explanation:
Use the mole = mass/mr equation to find the moles of CaO, then use the molar ratio to find the moles of Fe2O3, which is the same as CaO, (assuming the ratio is 1:1, as you haven't stated it clearly in the question). Then use the equation and input to find Mass, which is 98.8g to 3 s.f.
Explain how to count the number of elements in a compound.
Answer:
Simply identify what elements are in a compound
Explanation:
For example in NaCl we have sodium (Na) and Chlorine (Cl)
In order to do this you would need to recognise the symbols for a certain element: O for oxygen; N for nitrogen; H for hydrogen etc.
Use the Word Correctly in a Sentence
Ion
1. When _____
are added or removed from an atom, _____
is formed
Answer:
1.) protons or electrons 2.) ion
Explanation:
Consider the redox reaction below. Upper M g (s) plus Pper f e superscript 2 plus (a q) right arrow upper M g superscript 2 plus (a q) plus upper F e (s). Which equation is a half reaction that describes the reduction that is taking place?
Answer: [tex]Fe^{2+}(aq)+2e^-\rightarrow Fe(s)[/tex]
Explanation:
Oxidation reaction is defined as the reaction in which a substance looses its electrons. The oxidation state of the substance increases.
Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced.
[tex]Mg(s)+Fe^{2+}(aq)\rightarrow Fe(s)+Mg^{2+}(aq)[/tex]
The oxidation half reaction is:
[tex]Mg(s)\rightarrow Mg^{2+}(aq)+2e^-[/tex]
The reduction half reaction is:
[tex]Fe^{2+}(aq)+2e^-\rightarrow Fe(s)[/tex]
Answer:
A
Explanation:
edge
Which statement describes the solar feature shooting off into space labeled C?
An envelope of plasma surrounding the sun
A stream of glowing gas that shoots out from the sun in an arch
A brief eruption of intense high-energy radiation from the sun's surface
A dark spot appearing from time to time on the sun's surface
Answer:
The correct answer is - An envelope of plasma surrounding the sun.
Explanation:
In the provided diagram the C labeled part of the sun is an envelope of plasma surrounding the sun which is called Solar Corona which makes the outermost layer of the atmosphere of the sun. Solar Corona is hotter in comparison to the surface of the sun itself.
Solar Corona is made up of the fourth state of matter known as plasma that has its magnetic field that determined its structural characteristics. Thus, the correct answer is an envelope of plasma surrounding the sun.
Answer:
person above is correct
Explanation:
I took the quiz and got it right.
What percentage of the world's species of plants and animals can be found in the rainforest?
Answer:
50
Explanation:
please help there is a pic and marking brain list
Answer:
3
Explanation:
how does a balanced chemical equation satisfy the law of conservation of mass
Which of the following reactions had the greatest percent yield?
a.Theoretical yield 52.3 g; actual yield 50.7g
b.Theoretical yield 17.1 g; actual yield 15.7g
c.Theoretical yield 38.8 g; actual yield 36.2 g
d.Theoretical yield 24.6 g; actual yield 22.5 g
Answer:
Option A
Explanation:
As we know
Percent yield is the ratio of actual yield/theoretical yield
a) Percent yield - Theoretical yield 52.3 g; actual yield 50.7g = 0.97 = 97%
b) Percent Yield - Theoretical yield 17.1 g; actual yield 15.7g = 92%
c) Percent Yield - Theoretical yield 38.8 g; actual yield 36.2 g = 93%
d) Percent Yield - Theoretical yield 24.6 g; actual yield 22.5 g = 91%
Hence option A is correct
How do you explain the ability of nonmetals to attract electrons to themselves?
Answer:
When these chemical bonds form, atoms of some elements have a greater ability to attract the valence electrons involved in the bond than other elements. Electronegativity is a measure of the ability of an atom to attract the electrons when the atom is part of a compound. Electronegativity differs from electron affinity because electron affinity
HOPE IT HELPS
Explanation:
Answer:
it is electronegativity and it increases as you move up and to the right on the periodic table and nonmetals are situated to the top right of the periodic table
Explanation:
Please help due tomorrow science
Answer:
1. start line drawn in ink
2. start line below solvent level
Explanation:
1. the line would run up the paper. should have drawn with pencil.
2. the samples would dissolve into solvent and not run up the paper.
4. The volume of a gas is 2.5 L when the pressure is at standard pressure (101.325 kPa). What is the
volume of the gas if the pressure decreases to 85 kPa and the temperature of the gas if the pressure is constant?
Answer:
18.32L
Explanation:
sana makatulong
The image shows the ________ formula of methyl formate
a- structural
b-skeletal
c- molecular
d- empirical
Answer:
Structural formula
Explanation:
This is because structural formula is use to show or indicate chemical bonds that are present between atoms of molecules. structural formula comprises of symbols that represent the atoms which are connected by short lines which indicate the presence chemical bonds which could be single line, double lines or even triple lines.
Help!! < PHYSICAL SCIENCE>
i have a quiz yall help
How many moles are in a 18 L tank of nitrogen gas at STP?
Answer:
12
Explanation:
i feel like its 12 because moles are medium sized but are they adult moles or baby moles or growing moles
Mole measure the number of elementary entities of a given substance that are present in a given sample. Therefore, 0.803moles of nitrogen gas are there in a 18 L tank of nitrogen gas at STP.
What is mole?The SI unit of amount of substance in chemistry is mole. The mole is used to measure the quantity or amount of substance. We know one mole of any element contains 6.022×10²³ atoms which is also called Avogadro number.
Mathematically,
number of moles of any ideal gas =given volume ÷Volume occupied by one mole of a ideal gas at STP
Volume occupied by one mole of a ideal gas at STP=22.4L
given volume of nitrogen gas= 18 L
substituting all the given values in the above equation we get,
number of moles of nitrogen gas =18 L ÷22.4L
number of moles of nitrogen gas =0.803moles
Therefore, 0.803moles of nitrogen gas are there in a 18 L tank of nitrogen gas at STP.
To know more about mole, here:
https://brainly.com/question/15209553
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how many moles of solute are present in a 2 L of a 25M potassium nitrate solution
a. 0.5 moles
b. 2 moles
c. 50 moles
d. 25 moles
I NEED THIS ANSWER ASAP, im taking the quiz right now and i need HELPPP
Answer:
50 moles
Explanation:
took the quiz
Two parent reproduction involves cell division that includes ___________? *
Meiosis
Fibrosis
Mitosis
Answer:
Mitosis
Explanation:
If the pressure on a gas at -73°C is doubled but its volume is held constant, what will its final temperature be in degrees Celsius?
Answer:
127°C
Explanation:
This excersise can be solved, with the Charles Gay Lussac law, where the pressure of the gas is modified according to absolute T°.
We convert our value to K → -73°C + 273 = 200 K
The moles are the same, and the volume is also the same:
P₁ / T₁ = P₂ / T₂
But the pressure is doubled so: P₁ / T₁ = 2P₁ / T₂
P₁ / 200K = 2P₁ / T₂
1 /2OOK = (2P₁ / T₂) / P₁
See how's P₁ term is cancelled.
200K⁻¹ = 2/ T₂
T₂ = 2 / 200K⁻¹ → 400K
We convert the T° to C → 400 K - 273 = 127°C