Answer:
[tex]1.21\times 10^4[/tex] cal would be needed to heat 5.0 lbs of copper from 22 degrees C to 80.0 degrees C.
Explanation:
[tex]Q=m \times c \times \Delta T[/tex]
where
[tex]\Delta T[/tex] = Final T - Initial T
Q is the heat energy in calories
c is the specific heat capacity (for copper 0.092 cal/(g℃))
m is the mass of water
plugging in the values
[tex]$Q=5.01 b s \times 0.092 \frac{c a l}{g^{\circ} \mathrm{c}} \times\left(80.0^{\circ} \mathrm{C}-22^{\circ} \mathrm{C}\right)$[/tex]
Please Note:
1 lb = 453.592grams
So,
5 lbs = 5 × 453.592g = 2268 g
[tex]$\begin{aligned} Q &=2268 g \times 0.092 \frac{c a l}{g^{\circ} \mathrm{C}} \times 58^{\circ} \mathrm{C} \\\\ Q &=12102 \mathrm{cal} \end{aligned}$[/tex]
[tex]=1.21\times10^4[/tex] cal (Answer)
. Which substance is the limiting reactant when 2 g of S reacts with 3 g of O2 and 4 g of NaOH according to the following chemical equation: 2 S (s) + 3 O2 (g) + 4 NaOH (aq) → 2 Na2SO4 (aq) + 2 H2O (l) a) S (s) b) O2 (g) c) NaOH (aq) d) none of these substances is the limiting reactant.
Answer:
S is the limiting reagent.
Explanation:
To find the limiting reactant we must first write the balanced chemical reaction. It must be correctly balanced so that we can find the proper mole ratios.
2 S (s) + 3 O2 (g) + 4 NaOH (aq) → 2 Na2SO4 (aq) + 2 H2O (l)
After this we will convert our measurements to moles. For mass we do this by dividing by the molar mass.
2g ÷ 32.06 = 0.06238mol S
3g ÷ 32.00 = 0.09375mol O₂
Now that we have the moles of each of the reactants, we can multiply them by their mole ratio with a reactant.
0.06238mol S × 2/2 = 0.06238mol H2O
0.09375mol O₂ × 2/3 = 0.06250mol H2O
S is our limiting reagent because it makes the smaller amount of moles.
Which example is a way that intercellular communication occurs?
A: A molecule is sent through the plasmodesmata of a plant cell.
B: A molecule is transmitted from one part of a cell to another to cause a response.
C: A signal is translated into action for a muscle cell to contract.
D: A signal is sent down an exon within a nerve cell.
CORRECT Answer:
A molecule is sent through the plasmodesmata of a plant cell.
Explanation: K12 test.
I got it wrong because the other person who answered this question answered wrong so he/she made me get it wrong. :( :( :( :( :( :(
Multicellularity depends on intercellular communication. The membrane-lined channels known as plasmodesmata (PD) connect the cytoplasm of neighboring cells in plants, enabling direct molecular exchange. Thus, option A is correct.
What is role of plasmodesmata in plant cells?When it comes to intercellular trafficking, communication, and signaling for plant development and defense.
These pathways, referred to as plasmodesmata, enable chemicals to move freely between cells, allowing plants to grow regularly and form tissues and organs.
Plasmodesmata—intercellular pores that connect adjacent plant cells and permit membrane and cytoplasmic continuity—are crucial.
Therefore, A molecule is sent through the plasmodesmata of a plant cell.
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Compared to the entire atom ,the nucleus of the atom
Answer:
C- smaller and contains most of the atom's mass.
Compared to the entire atom, the nucleus of the atom is:
C. Smaller and contains most of the atom's massAn atom is the tinitest way a matter can be broken down into. Atoms can either be negatively or positively charged. An atom is made up of:Protons (positive charge)Electrons (negative charge)Neutrons (no charge)The nucleus of an atom is the part of the atom that contains the protons and the neutrons at the middle of the atom.The mass of an atom is the size of the atom and the SI unit is measured in kilograms.As a result of this, when compared to the entire structure of the atom, the nucleus of the atom is smaller,but contains most of the mass of the atom.Therefore, the correct answer is option C.
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How many moles of water are represented in a breaker containing 45.9g H2O
Answer:
There are 2.55 moles of water.
Explanation:
First you have to calculate the molar mass fo water ⇒ 18 grs/mol.
Then 18 grs ----------- 1 mol H2O
45.9 grs ------- 2.55 moles of H2O
There are 2.55 moles of water.
A piper delivers 9.98 g of water at 19 degrees Celsius. What does the pipet deliver
Answer:
9.99 ml water will be delivered from pipet
Explanation:
When Water is being delivered by the pipet the temperature is 19 degree Celsius. Also know that dependence of density is on temperature although this temperature dependence is inverse in nature that is when temperature increases density decreases and vice versa.
Now we also know the density of water at 20 ° Is [tex]0.99 gml-1[/tex].
At this temperature 9.98 gram will occupy a volume= [tex]0.98/0.998= 9.997ml[/tex]
An atom of argon rarely bonds to an atom of another element because an argon atom has
Answer:
The answer to your question is below: 8 electron in its outer most shell.
Explanation:
Argon like noble gases are stable elements that means that they do not react with other elements. They have eight electrons in their outermost shell; Elements are stable when they reach 8 electronsin their outer most shell, some elements reach 8 electrons receiving from others (nonmetals) and others donate electrons ( metals).
1. Why do scientists use a common system of measurement?
Answer:
so measuring stuff is easier and simple
Explanation:
Platinum has a density of 21.45 G / CC. gold has a density of 19.3 G / CC.
a) which is larger 100 gram cube of platinum or a hundred grand cube of gold?
b) what is the length of each side of a 100 gram cube of platinum?
Answer:
The answer to your question is:
a) The gold cube is larger.
b) lenght = 1.67 cm
Explanation:
Data
Platinum density 21.45 g/cm3 100 gram cube
Gold density 19.3 g/cm3 100 gram cube
Formula
density = mass / volume
a) Calculate volume
volume = mass / density
Platinum volume = 100 / 21.45 = 4.66 cm3
Gold volume = 100 / 19.3 = 5.18 cm3
b) Volume = lenght³
4.66 cm³ = lenght³
lenght = ∛4.66
lenght = 1.67 cm
A 100-gram cube of gold would be larger than a 100-gram cube of platinum because gold has a lower density than platinum. The length of each side of a 100-gram cube of platinum would be approximately 1.67 cm.
Explanation:Answer:
a) Which is larger, a 100-gram cube of platinum or a 100-gram cube of gold?
The gold cube would be larger. This is because gold has a lower density than platinum, meaning that a certain mass of gold will occupy a larger volume than the same mass of platinum.
b) What is the length of each side of a 100 gram cube of platinum?
To answer this, you would first calculate the volume of the cube using the density and mass. The formula to do this is mass/density = volume. So, 100 grams / 21.45 g/cm³ = approximately 4.66 cm³. Now, because it is a cube and all sides are equal, take the cube root of this volume to get the length of each side. The cube root of 4.66 cm³ is about 1.67 cm. Thus, each side of the 100 gram platinum cube would be approximately 1.67 cm.
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Which statements accurately describe atoms? Check all that apply.
Atoms cannot be divided.
There are only a few different types of atoms.
A single atom can be seen using a standard microscope.
Atoms were named in the fifth century BCE.
Atoms are the smallest unit of matter.
Answer:
- Atoms cannot be divided
- Atoms were named in the fifth century BCE
- Atoms are the smallest unit of matter
Explanation:
- The atom is widely known as the smallest unit matter is made of, which obtains properties of a chemical element.
- Atom can be regarded as indivisible amount of a chemical element having its own existance.
- All states of matter are made of neutral or ionized atoms.
- In the 5th century BCE, the basic concept of atom was by the atomist school in Ancient Greece.
The molar mass of nitrogen (N2) is 28.02 g/mol. What is the mass, in grams, of 4.60 mol of Nz?
0.164
6.09
23.4
129
Answer: 129
Explanation:Please see attachment for explanation
which is a family with nonmetals whose atoms gain or share one electron in chemical reactions
The yogurt bacteria are usually Gram-positive, which means the Gram staining process dyes them ________.
Practice
A
blue
B
green
C
purple
D
pink
Answer:
The staining process will dye them purple (option C)
Explanation:
Gram staining is a method of staining used to distinguish and classify bacterial species into two large groups. Those 2 groups are called Gram- positive and gram - negative groups.
This staining is based on the composition of their cell wall. Gram staining uses crystal violet to stain cell walls, iodine as a mordant, and a fuchsin or safranin counterstain to mark all bacteria.
⇒ Gram- positive bacteria are called gram - positive because they will give a positive result. This according to their cell wand. Their cell wall is typically rich with peptidoglycan and lacks the secondary membrane and lipopolysaccharide layer found in Gram-negative bacteria
Gram- positive bacteria take up the crystal violet stain used in the test, and then appear to be purple-coloured.
⇒ Gram- negative bacteria are called gram - negative because they will give a negative gram result.
Because of the presence of higher lipid content, after the alcohol-treatment, the porosity of the cell wall increases, hence the CVI complex (crystal violet – iodine) can pass through. Thus, the primary stain (crystal violet) is not retained. Gram negative bacteria will appear red or pink.
Yogurt is produced using a culture of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. (In addition, other lactobacilli and bifidobacteria). All of those bacteria are gram-positive, what means they will appear purple.
Which situation is an indication that a chemical change has occurred?
A. A gas is formed.
B. No heat is released.
C. The temperature does not change.
D. No color change occurs.
Heat is released.
When a chemical change occurs, energy comes out of the atoms which causes heat.
Answer: Option (A) is the correct answer.
Explanation:
Chemical changes are defined as the change which tend to show difference in chemical composition of a substance.
For example, toxicity, reactivity, combustion etc are all chemical properties.
So, in the given situation formation of bubbles shows that a gas has been formed which is a chemical change.
A chemical change will always lead to the formation of a new compound and this change is irreversible in nature by any physical means.
On the other hand, a change which is unable to bring any difference in chemical composition of a substance is known as a physical change.
For example, change in shape, size, mass, volume etc are all physical properties.
Thus, we can conclude that a gas is formed is an indication that a chemical change has occurred.
Which graph best shows the relationship between kelvin temperature and average kinetic energy?
Answer:
The Kelvin temperature scale reflects the relationship between temperature and average kinetic energy.
Explanation:
The Kelvin temperature of a substance is directly equal to the average kinetic energy of the particles of a substance.
Answer:
Is a direct relation among them
Explanation:
As you increase the kinetic energy of the molecules, the temperature will increase, if the molecules have more energy, will move faster.
Check the graphic.
When the particles absorb some energy from the surroundings, it will start to save it, until the element do not want to be in a compound or in a certain state of matter, it will be independent
Hope this info is useful.
Which particles make up the nucleus of an atom?
A. protons and electrons
B. neutrons and electrons
C. protons only
D. protons and neutrons
E. neutrons only
D. Protons and neutrons.
Happy to help! Please mark as BRAINLIEST! Thanks
Answer:
protons and nuetrons
Explanation:
oh god i swear i'm usually not this dumb but pls help!
A group of students is investigating whether copper is a better thermal conductor than steel. The students take a copper wire and a steel wire of the same length and diameter. They put equal lengths of wax on one end of each wire and dip the other end into a beaker of hot water. The length of wax left on the wires after 10 minutes is shown.
Experimental Observations:
Copper:
Original Length of Wax: 3cm
Length of Wax After 10 Minutes: 0.7cm
Steel:
Original Length of Wax: 3cm
Length of Wax After 10 Minutes: 1.8cm
What was the dependent variable in this experiment?
Type of wire used
Original length of wire
Original length of wax
Thermal conductivity of wire
i think it's c??
Answer:
Thermal Conductivity
Explanation:
The dependent variable is what is being measured in the experiment and it's affected by the independent variable. Thermal conductivity is the best answer, because you are trying to find out which wire is a better conductor of thermal conductivity. Basically, which one conducts more heat? The copper does, because when its put into the hot water it melted more of the wax than the steel wire did.
Answer: Thermal conductivity of wire
Explanation:
The hypothesis of the experiment is to find the thermal conductivity of the the wires. The independent variable in the experiment is the type of wire used.
There are two types of wire used in the experiment one is copper and other one is steel. Rest all the variables are control variable.
At the end of the experiment the thermal conductivity was determined. This is the dependent variable of the experiment.
Hence, the correct answer is option D
An antacid tablet added to a glass of water fizzes and bubbles as it mixes.
Which of the indicators of a chemical change is represented in this scenario?
A) formation of a precipitate
B) change in energy
C) formation of a gas
D) change in color
Answer:
B is wrong
Explanation:
I took a test just now and got it wrong
The indicators of a chemical change are represented in this scenario is the formation of a gas.
What is a chemical change?A chemical change is a change in the substance's chemical properties and its physical properties. The chemical changes show that a chemical reaction occurred.
Thus, the correct option is C) formation of a gas.
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f(x) = 2x - 5
g(x) = 3x2 + 2
Find (f ·g)(x)
Answer:
g(x) = 2 always
Explanation
No matter the value, even if you write F(x), its value is always 2! SKSKSKSKS PERIOD !!!!!
The product of the two functions f(x) and g(x), represented as (f · g)(x), is found by multiplying the equations together. The resulting equation after applying distributive property is 6x^3 - 15x^2 + 4x - 10.
Explanation:The question asks for the product of two functions, f(x) and g(x). This is denoted as (f · g)(x), which is the multiplication of respective function values.
The functions given are f(x) = 2x - 5 and g(x) = 3x^2 + 2. To find (f · g)(x), we multiply these two functions together.
(f · g)(x) = (2x - 5)(3x^2 + 2).
Using distributive property, the result is: 6x^3 + 4x - 15x^2 - 10
So, (f · g)(x) = 6x^3 - 15x^2 + 4x - 10 is the product of the two functions.
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When explaining chemical reactions to a friend, Brianna models a reaction by taking several colors of modeling clay and making a sculpture of a horse. Which type of chemical reaction is Brianna most likely explaining?
Answer:
In the given question Brianna is trying to make a whole figure by combining different single elements.
Explanation:
Here are the different coloured that are used to join and make one piece this method that Brianna is following is called synthesis.
The combination here is of simple substances that are combined directly to make a complex compound. The compound formed is complex while the substances that combined together can be element or compound or a combination of both.
Answer: synthesis
Explanation:
What is the net force acting on the box
Answer:
According to Mr. Newton, an object will only accelerate if there is “net force” acting upon it. A net force is the sum of all forces acting on an object. A net force is capable of accelerating a mass.
Explanation:
Which statements below are an appropriate hypothesis in response to this question? Check all that apply. If a substance changes state of matter (e.g., liquid to gas), then this is a physical change because the original properties of the substance have not changed. If a substance undergoes a physical change, then it will retain most of its original properties because no new substance is formed. If a substance undergoes a chemical change, then it will not retain its original properties because a new substance is formed. If a precipitate is formed when two substances are mixed, then a chemical change has taken place because precipitates are new substances.
Answer:
If a substance undergoes a physical change, then it will retain most of its original properties because no new substance is formed.
If a substance undergoes a chemical change, then it will not retain its original properties because a new substance is formed.
Explanation:
So in shorter words its options 2 and 3
All four statements are appropriate hypotheses reflecting the distinctions between physical and chemical changes. Physical changes involve alterations in the state or form without changing the chemical identity, whereas chemical changes result in the creation of new substances.
Explanation:When addressing the question regarding whether certain statements about physical and chemical changes are appropriate hypotheses, it's important to recognize that an appropriate hypothesis should be testable and based on scientific concepts. The statements provided can be evaluated based on our understanding of physical and chemical properties and changes.
If a substance changes state of matter (e.g., liquid to gas), then this is a physical change because the original properties of the substance have not changed.If a substance undergoes a physical change, then it will retain most of its original properties because no new substance is formed.If a substance undergoes a chemical change, then it will not retain its original properties because a new substance is formed.If a precipitate is formed when two substances are mixed, then a chemical change has taken place because precipitates are new substances.These statements align with the fundamental distinctions between physical and chemical changes. A physical property change affects the form but not the chemical identity of a substance, whereas a chemical property change results in the formation of a new substance.
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What type of rock is calcite?
А) igneous
В) sedimentary
C) metamorphic
D) It's not a rock.
Calcite comes from limestones and limestones are sedimentary.
So calcate is sedimentary rock
Which of the following is an example of qualitative
A each mouse in the study lived for 3 years.
B each mouse In the study was 75 cm long.
C each mouse in the study has brown ears.
D each mouse in the study ate four times a day.
Answer:
Option =C each mouse in the study has brown ears.
Explanation:
Qualitative:
Qualitative properties are those that can be only observed but not measured in numerical values. These are observed through senses: touch, sight, smell, taste and hear.
For example:
Color, odor, brittleness, taste etc.
Quantitative:
Quantitative properties can be measured in numerical values.
For example:
Melting point, boiling point, conductivity, viscosity, density, hardness and solubility.
In short we can say that qualitative is a measure of quality while the quantitative is a measure of quantity.
If a 30 kg child were running at a rate of 9.9 m/s, what is his KE?
Answer:
30 kg x 9.9m/s=297 N
Explanation:
When, a 30 kg child were running at a rate of 9.9 m/s, then child's kinetic energy is 1470.15 joules.
The student's question is concerned with calculating the kinetic energy (KE) of a child running at a certain speed. Kinetic energy can be calculated using the formula KE = (1/2)mv₂, where m is mass and v is velocity. In this case, since the student has provided the values of the child's mass (30 kg) and the speed (9.9 m/s), we can compute the kinetic energy.
First, square the velocity: 9.9 m/s imes 9.9 m/s = 98.01 m/s². Next, multiply this value by the mass of the child and then divide by 2 to get the final kinetic energy:
KE = (1/2)imes 30 kg imes 98.01 m2/s2 = 1470.15 J (joules).
Therefore, the kinetic energy of a 30 kg child running at 9.9 m/s is 1470.15 joules.
A scientist read about an experiment done by someone else. She does the same experiment in her lab to make sure it works.
This is an example of
Answer:
It’s Replication
Explanation:
If someone conducts an experiment which is done once already at the same conditions and criterias, it can be said as replicating the experiment. Hence, this is an example of replication of the experiment.
What is replication of an experiment?Replication is the act of repeating an experimental setup in order to gauge the phenomenon variability. As defined by ASTM in standard E1847, replication is "the repetition of the entire set of the experimental treatment combinations to be compared. A replicate is one of the repeats."
Repeated measurements of the same item are not the same as replication since they are handled differently in statistical experimental design and data processing.
Single-item testing or evaluation may not be representative of a batch or process and does not account for item-to-item variation. Therefore, repeating the same experiment to test the productivity of the results of an experiment is called replication.
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Which of the following is equal to 1 meter?
Answer:
What following????
Explanation:
Answer:
Can you be more specific
Explanation:
8. When a 2.5 mol of sugar (C12H22O11) are added to a certain amount of water the boiling point is raised by 1 Celsius degree. If 2.5 mol of aluminum nitrate is added to the same amount of water, by how much will the boiling point be changed? Show all calculations leading to your answer OR use 3 – 4 sentences to explain your answer.
Answer:
The boiling point of the water by adding 2.5 moles of aluminium nitrate will be changed by 4° C.
Explanation:
Step 1: define the formula for an elevation of the boiling point
Δ T b = i *K b *bB
⇒with Δ T b = the elevation of the boiling point ( in °C or Kelvin)
⇒with i = van't Hoff i -factor for the solute. The factor i shows the number of individual particles (typically ions) that are formed by a compound in the solution.
⇒ with Kb = ebullioscopic constant, which depends on the properties of the solvent. (Eventually can be calculated).
⇒ with bB= the molal concentration (molality) of the solute.
Since we have 2 different solutions ( component 1 = sugar and component 2 = aluminium nitrate) of the same molality in the same solvent ( water). We can express this as followed:
Δ T b,2 / Δ T b,1 = (i2 * Kb * bB ) / (i1 * Kb *bB)
⇒after he was simplifying this becomes:
Δ T b,2 / Δ T b,1 = i2 / i1
⇒ Now we can isolate either Δ T b,2 or Δ T b,1:
Δ T b,2 =(i2/i1) x Δ T b,1
Sugar
⇒ is a covalent compound, so it doesn't dissociate in water ⇔ i1=1
Aluminium nitrate
⇒ it's a soluble ionic compound and in solution it will dissociate as the following equation:
Al(NO3)3 (aq) → Al3+(aq) + 3NO3- (aq)
⇒thus here are 4 particels formed : 1 Al3+ + 3NO3-
i2=4
As given, we also know that the temperature was raised by 1°C after adding sugar ⇒ Δ T b,1 = 1°C
Step 2: insert all the numbers in the formula for boiling point elevation
(i2/i1) x Δ T b,1
(4/1 ) x 1°C = 4°C
⇒ The boiling point of the water by adding 2.5 moles of aluminium nitrate will be changed by 4°C
A 0.5895-g sample of impure magnesium hydroxide is dissolved in 100.0 mL of 0.2050 M HCl solution. The excess acid then needs 19.85 mL of 0.1020 M NaOH for neutralization. Calculate the percent by mass of magnesium hydroxide in the sample, assuming that it is the only substance reacting with the HCl solution. (Can some please show all the steps to this with the answer? I’m completely lost).
Answer:
91.38 %
Explanation:
First we use the following formula to calculate the number of moles of HCl and NaOH contained in the solutions:
molar concentration = number of moles / solution volume
number of moles = molar concentration × solution volume
number of moles of HCl = 0.2050 × 100 = 20.5 mmoles
number of moles of NaOH = 0.1020 × 19.85 = 2.02 mmoles
reaction between NaOH and HCl:
NaOH + HCl → NaCl + H₂O
If 2.02 mmoles of NaOH were used for neutralization of HCl left from the reaction, which are 2.02 mmoles of HCl, it means that the HCl reacted with Mg(OH)₂:
20.5 - 2.02 = 18.48 mmoles of HCl
2 HCl + Mg(OH)₂ = MgCl₂ + 2 H₂O
From the chemical reaction we devise the following reasoning:
if 2 mmoles of HCl react with 1 mmole of Mg(OH)₂
then 18.48 mmoles HCl react with X mmoles of Mg(OH)₂
X = (18.48 × 1) / 2 = 9.24 mmoles of Mg(OH)₂
now the mass of Mg(OH)₂:
mass = number of moles × molecular weight
mass of Mg(OH)₂ = 9.24 × 58.3 = 538.7 mg = 0.5387 g
Now the percent by mass of magnesium hydroxide Mg(OH)₂ in the impure sample (purity):
purity = (mass of pure Mg(OH)₂ / mass of impure sample) × 100
purity = (0.5387 / 0.5895) × 100
purity = 91.38 %
To calculate the percent by mass of magnesium hydroxide in the sample, determine the number of moles, and multiply by 100 to get the percent.
Explanation:To calculate the percent by mass of magnesium hydroxide in the sample, we need to determine the number of moles of HCl that reacted with the magnesium hydroxide. We can use the stoichiometry of the reaction to find the moles of magnesium hydroxide. Then, we can divide the mass of magnesium hydroxide by the mass of the sample and multiply by 100 to get the percent.
The balanced chemical equation for the reaction is:
Mg(OH)2(s) + 2HCl(aq) → MgCl2(aq) + 2H2O(l)
Using the molar ratio from the balanced equation, we can calculate the number of moles of magnesium hydroxide:
2 moles of HCl react with 1 mole of Mg(OH)2
moles of Mg(OH)2 = moles of HCl * (1 mole of Mg(OH)2 / 2 moles of HCl)
Finally, we can calculate the percent by mass of magnesium hydroxide in the sample:
Percent by mass = (mass of magnesium hydroxide/mass of sample) * 100%
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Describe the composition of common amino acids.
Answer:
Explanation:
Amino acids consist of an amine (-NH2) group and a carboxyl acid (-COOH) group. So they have elements such as Nitrogen (N), Hydrogen (H), Carbon (C) and Oxygen (O).
Amino acid composition:
NitrogenCarbonHydrogenOxygenThe human body has 20 amino acids which are all important but there are only 9 that are essential for the human body.
Best of Luck!
How many magnesiums, Oxygens and hydrogens does Mg(OH)2 have?