Answer:
None have backbones
No cell walls
Multicellular
Includes radial or bilateral body symmetry.
Explanation:
What mass of hydrogen is required to react with 24.7 g of nitrogen?
Answer:
10.80 g of H2
Explanation:
As per the equation, let us calculate the mole ratio. N2+3H2→2NH3. As per the equation one mole of nitrogen
How did Mendeleev arrange the known elements in his periodic table? O A. According to the number of protons O B. According to the number of electrons O C. According to atomic mass O D. According to atomic number
Mendeleev arranged the known elements in his periodic table according to atomic number (option D).
What is the periodic table?Periodic table is a tabular chart of the chemical elements according to their atomic numbers so that elements with similar properties are in the same group (column).
The chemical elements are organized by atomic number, from the element with the lowest atomic number, hydrogen, to the element with the highest atomic number, oganesson.
Dmitri Mendeleev is the Russian scientist that formulated the periodic table of chemical elements and arranged them in order of increasing atomic number.
Learn more about periodic table at: https://brainly.com/question/11155928
#SPJ1
Answer: C.
Explanation:
according to atomic mass
The successive ionization energies for a given element are listed. How many valence electrons does it have?
Answer:
3 valence electrons
Explanation:
Let us first find the amount increased for everything.
From 1st to 2nd, 1048 - 620 = 428
428 increased from 1st to 2nd.
From 2nd to 3d, 2144 - 1048 = 1096
1096 increased from 2nd to 3rd.
From 3rd to 4th, 8724 - 2144 = 6580
6580 increased from 3rd to 4th.
From 4th to 5th, 10141 - 8724 = 1417
From 3rd to 4th, it increased the most. Therefore, we assume that those are the beginning core electrons and not valence electrons. Also, starting from 3rd, they are all core electrons.
For the 1st and 2nd, we can assume they are valence electrons because the kJ/mol didn't increase that much.
Since the core electrons started from the 3rd, we most likely have 3 valence electrons.
So the final answer is 3.
Hope it helped!
Which element has the greatest average atomic mass?
Answer:
Tellurium
Explanation:
Edg 2021
Is this structure named correctly???
Pls answer me fast guys!!
Answer:
No; According to the IUPAC , it should be
3-bromopentan-2-olConsider the reaction of solid aluminum iodide and potassium metal to form solid potassium iodide and aluminum metal.The balanced chemical equation is AlI₃(s) + 3 K(s) → 3 KI(s) + Al(s).Given the reaction has a percent yield of 67.8%, what is the mass in grams of aluminum iodide that would be required to yield an actual amount of 30.25 grams of aluminum?
Answer:
674.26 g of AlI₃
Explanation:
We'll begin by calculating the theoretical yield of aluminum (Al). This can be obtained as follow:
Percentage yield of Al = 67.8%
Actual yield of Al = 30.25 g
Theoretical yield of Al =?
Percentage yield = Actual yield /Theoretical yield × 100/
67.8% = 30.25 / Theoretical yield
67.8 / 100 = 30.25 / Theoretical yield
0.678 = 30.25 / Theoretical yield
Cross multiply
0.678 × Theoretical yield = 30.25
Divide both side by 0.678
Theoretical yield = 30.25 / 0.678
Theoretical yield of Al = 44.62 g
Next, we shall determine the mass of AlI₃ that reacted and the mass of Al produced from the balanced equation. This can be obtained as follow:
AlI₃(s) + 3K(s) → 3KI(s) + Al(s)
Molar mass of AlI₃ = 27 + (3×127)
= 27 + 381 = 408 g/mol
Mass of AlI₃ from the balanced equation = 1 × 408 = 408 g
Molar mass of Al = 27 g/mol
Mass of Al from the balanced equation = 1 × 27 = 27 g
Summary:
From the balanced equation above,
408 g of AlI₃ reacted to produce 27 g of Al.
Finally, we shall determine the mass of
AlI₃ required to produce 44.62 g of Al. This can be obtained as follow:
From the balanced equation above,
408 g of AlI₃ reacted to produce 27 g of Al.
Therefore, Xg of AlI₃ will react to produce 44.62 g of Al i.e
Xg of AlI₃ = (408 × 44.62)/27
Xg of AlI₃ = 674.26 g
Thus, 674.26 g of AlI₃ is needed for the reaction.
2.92 x 10^-15/
(5.6 x 10^-3) (4.16 x 10^9)
Answer:
3645.46
Explanation:
calculated
what happen when we put a waterproof paper in hot water and what happens in cold water?
Answer:
When you heat up water, the water molecules start moving around faster and faster. ... So hot water is less dense than cold water. When you put the two together with the hot water on the bottom, the hot water rises to the top, mixing with the cold water along the way and creating purple water.
Explanation:
have a great day :)
(1) Phosphorus silicon is a semi-conductor
When Silicone is altered with Phosphorus, 4 of its electrons form covalent bonding and the 5th electron becomes delocalized and thus it increases electrical conduction
Answer:
blue blah blue blah
Explanation:
why is the difference between the result for an ideal gas and that calculated using the van der waals equation greater when the gas is confined to 5.00 L compared to 22.4 L
The question is incomplete, the complete question is;
In Sample Exercise 10.16, we found that one mole of Cl2 confined to 22.41 L at 0 °C deviated slightly from ideal behavior. Calculate the pressure exerted by 1.00 mol Cl2 confined to a smaller volume, 5.00 L, at 25 °C. (a) First use the ideal-gas equation and (b) then use the van der Waals equation for your calculation. (Values for the van der Waals constants are given in Table 10.3.) (c) Why is the difference between the result for an ideal gas and that calculated using the van der Waals equation greater when the gas is confined to 5.00 L compared to 22.4 L?
Answer:
See explanation
Explanation:
Since we have
For 5.00 L using Ideal gas law;
PV= nRT
P = nRT/V
P = 1 * 0.082 * 298 K/5.00
P= 4.887 atm
Using Van der walls equation;
[P + an^2/v^2] * [V - nb] = nRT
P = (nRT/ [V - nb]) - (an^2/v^2)
P= 1 * 0.082 * 298/5 - (1 * 0.0562) - (6.49(1^2)/5^2)
P = (24.436/4.9438) - 0.2596
P= 4.683 atm
For 22.4 L
P = nRT/V
P = 1 * 0.082 * 298 K/22.4
P= 1.0909 atm
Using Van der Walls equation;
[P + an^2/v^2] * [V - nb] = nRT
P = (nRT/ [V - nb]) - (an^2/v^2)
P= 1 * 0.082 * 298/22.4 - (1 * 0.0562) - (6.49(1^2)/22.4^2)
P= (24.436/ 22.3438) - 0.0129
P= 1.081 atm
According to Boyle's law, pressure is inversely proportional to volume. Increase in volume leads to decrease in pressure. Therefore the pressure calculated both by the ideal gas equation and Van der Waals equation at 5.00 L is greater than that calculated using both methods at 22.4 L
Covalent bonding occurs between atoms when 1. The potential energy of the shared elec- trons is lower in the bond than it would be if the electrons were not shared between two nuclei 2. The potential energy of the shared elec- trons is independent of the covalent bond, but the potential energy of the newly formed molecule is greater than the individual atoms 3. Covalent bonding occurs when the octet rule is satisfied regardless of the potential en- ergy of the shared electrons 4. The potential energy of the shared elec- trons is higher in the bond than it would be if the electrons were not shared between two nuclei
Answer:The potential energy of the shared elec- trons is lower in the bond than it would be if the electrons were not shared between two nuclei
Explanation:
The entire essence of chemical combination is the attainment of a lower potential energy.
When two atoms are isolated at a large distance from each other, the potential energy is high.
However as the nuclei of the two atoms approach each other, the potential energy decreases until a minimum is attained. The distance between the nuclei at this point is the bond distance.
Hence, the potential energy of the shared electrons is lower in the bond than it would be if the electrons were not shared between two nuclei.
Hydrogen bromide is a chemical compound. It’s formed from atoms of hydrogen and bromide, two
A
electrons.
B
elements.
C
neutrons.
D
nuclei.
Answer: The correct option is B. elements.
Explanation:
A chemical compound is defined as the specie which is formed by the combination of two or more elements. For example: Water, carbon dioxide, etc..
Elements is defined as the chemical specie which consists of only one type of atom. For example: Hydrogen, Oxygen, etc..
Now, when hydrogen element and bromine element combines, it leads to the formation of a heteronuclear chemical compound known as hydrogen bromide having chemical formula HBr.
Hence, the correct option is B. elements.
Hydrogen and bromine are two elements that form hydrogen bromide (HBr).
COMPOUND:
A compound is a chemical substance made up of chemical combination of two or more elements. According to this question, Hydrogen bromide is a chemical compound formed from atoms of hydrogen (H) and bromine (Br). These two atoms that make up hydrogen bromide are that of elements. Therefore, it can be said that hydrogen and bromine are two elements that form hydrogen bromide (HBr).Learn more at: https://brainly.com/question/13516179?referrer=searchResults
_____________________________________ are changes in an organism’s genetic material.
Answer:
The answer is Evolution.
Evolution is a process that results in changes in the genetic material of a population over time. Evolution reflects the adaptations of organisms to their changing environments and can result in altered genes, novel traits, and new species.
What does a sound wave’s frequency tell you? HELP IF YOU WANT BRAINLEIST AND TO HAVE YOUR COMMENT LIKED!!
A. the loudness or softness of the sound from an object
B. the type of medium in which the sound is traveling
C. the number of vibrations per second an object is making
D. the amplitude of the sound wave
Answer:
I am pretty sure it is C.
Explanation:
Because the wave frequency's tell us the number of waves there are on that diagram.
Answer:
C. the number of vibrations per second an object is making
Explanation:
Hope this helps. Sorry if it doesn't. T^T
what is bohr's model?
Answer:
In atomic physics, the Bohr model or Rutherford–Bohr model, presented by Niels Bohr and Ernest Rutherford in 1913, is a system consisting of a small, dense nucleus surrounded by orbiting electrons—similar to the structure of the Solar System, but with attraction provided by electrostatic forces in place of gravity.
Answer:
BOHR'S MODEL OF ATOM :
In order to overcome the objections raised against Rutherford's model of the atom, Neils Bohr put forward the following postulates about the model of an atom:
(i) Only certain special orbits known as discrete orbits of electrons, are allowed inside the atom.(ii) While revolving in discrete orbits the electrons do not radiate energy.These orbits or shells are called energy levels. Energy levels in an atom are shown in Fig.
There orbis for shells are represented by the letters K,L,M,N... or the number n = 1,2,3,4...
ABOUT BOHR :
Neils Bohr (1885-1962) was born in Copenhagen on 7 October 1885. He was appointed professor of physics at Copenhagen University in 1916. He got the Nobel prize for his work on the structure of atom in 1922. Among Professor Bohr's numerous writings. three appearing
s books are:
(i) The Theory of Spectra and AtomicConstitution. (ii) Atomic Theory and.(iii) The Description of Nature————————————————Atoms are stationary and don't move when in solid form.
False
True
Answer:
True? The don't stay exactly still i dont think, but i'd say true.
Explanation:
Answer:
TRUE
Explanation:
In a solid, atoms are packed tightly together and move very slowly. In fact, they do not flow at all: they simply vibrate back and forth.
Key words vibrate, not movement.
Correct me if I'm wrong of course
PLS HELP ASAP THIS IS DUE TODAY
Answer: what grade are u in ill help
Explanation:
Use the following reaction:
6 NaCl + Ba3(PO4)2 → 2 Na3PO4 + 3 BaCl2
How much barium chloride is produced (in g) when 1500 g of sodium chloride react with excess barium phosphate?
Round your answer to a whole number, do not write the units.
Mass of Barium chloride produced : 2666.56 g
Further explanationGiven
Reaction
6 NaCl + Ba3(PO4)2 → 2 Na3PO4 + 3 BaCl2
1500 g of sodium chloride
Required
Barium chloride produced
Solution
mol NaCl (MW= 58.5 g/mol) :
mol = mass : MW
mol = 1500 g : 58.5 g/mol
mol = 25.64
mol Barium chloride-BaCl2 based on mol NaCl(as a limiting reactant)
From the equation, mol ratio NaCl : BaCl2 = 6 : 3, so mol BaCl2 :
[tex]\tt \dfrac{3}{6}\times 25.64=12.82[/tex]
mass BaCl2(MW=208 g/mol) :
mass = mol x MW
mass = 12.82 x 208
mass = 2666.56 g
Which of the following describes hetereogeneous mixture... 1)A mixture that is easily separated, the components are different sixes and unevenly mixed. 2) A mixture that is very difficult to separate, the contents are evenly mixed and the mixture looks like a substance
Answer:
1)A mixture that is easily separated, the components are different sixes and unevenly mixed.
Explanation:
Mixtures are impure substances with usually indefinite composition. Their constituents often retains their identities. They can easily be separated into constituents by physical methods.
Homogenous mixtures have their constituents existing in only one phase.
Heterogeneous mixtures have their constituents existing in at least two different phases.
Heterogenous mixtures are easily separated due to the phase differences of its constituents. They are easily separated by physical processes compared to homogeneous mixtures.PLEASE HELP I WILL GIVE YOU BRAINLIEST
(the linked photo)!!! thank you
Answer:
1. nitrous oxide
2. copper sulfide
3. cl2o7
4. MgBr2
Explanation:
hope it helps
Which of the following atoms has the greatest tendency to attract electrons?
A. Sodium
B. Magnesium
C. Boron
D. Sulfur
Answer: b!
Explanation:
What is the molecular formula for a compound with a molar mass of 42.08g/mol and an empirical formula of ch2
Answer:
[tex]C_3H_6[/tex]
Explanation:
Hello!
In this case, since the empirical formula is the smallest representation of the molecular formula, it is known that the times in which the empirical formula is into the molecular formula is a whole number and is computed by dividing the molar mass of the molecular formula by that of the empirical formula as shown below:
[tex]\frac{42.08g/mol}{12.01+1.01x2}= \frac{42.08g/mol}{14.03g/mol}=3[/tex]
Thus, the molecular formula times the empirical formula by 3 to obtain:
[tex]C_3H_6[/tex]
Regards!
11. Everybody loves Mr Brown
Answer:
NO I DON'T ✌✌✌✌✌✌✌✌✌
Which electron configuration is impossible?
a. ls22s22p2d2
b. 1s22s22p63s23p64s
c. 1s22s22p63s23p3
d. 1s22s22p63s2
e. 1s22s22p63s23s54s
1
Answer:
MP hippopotamus
Explanation: I'm in the fifth grade so yeah I really don't know this so I'm just going to say some random stuff and white cheddar mac and cheese warm TV perfect back MD 11443 to 2885 eleven 12:20 to 11 132 0.24 answer
A 52 gram sample of an unknown metal requires 714 Joules of energy to heat it from
30.5◦C to 82◦C. What is the specific heat of
this metal?
Answer in units of J/g ·
◦ C.
Answer: Approximately [tex]0.267 \frac{\text{J}}{\text{g}^{\circ}\text{C}}[/tex]
===================================================
Work Shown:
We have the following variables
Q = 714 joules = heat requiredm = 52 grams = massc = specific heat = unknown[tex]\Delta t[/tex] = 82-30.5 = 51.5 = change in temperaturenote: the symbol [tex]\Delta[/tex] is the uppercase Greek letter delta. It represents the difference or change in a value.
Apply those values into the formula below. Solve for c.
[tex]Q = m*c*\Delta t\\\\714 = 52*c*51.5\\\\714 = 52*51.5*c\\\\714 = 2678*c\\\\2678*c = 714\\\\c = \frac{714}{2678}\\\\c \approx 0.26661687826737\\\\c \approx 0.267\\\\[/tex]
The specific heat of the unknown metal is roughly [tex]0.267 \frac{\text{J}}{\text{g}^{\circ}\text{C}}[/tex]
A family requires 20,000 KJ of fuel energy every day. If calorific vlaue
of the fuel used by them is 15,000 kJ/kg, how much of this fuel will be
required by this family to meet their energy needs for the month of April?
Answer:
40 kilograms of fuel are required to meet their energy needs for the month of April.
Explanation:
The month of April has 30 days and the full energy needed by the family is determine by the following combustion formula, derived from dimension analysis:
[tex]n\cdot Q = m\cdot L_{c}[/tex] (1)
Where:
[tex]m[/tex] - Mass of the fuel, measured in kilograms.
[tex]L_{c}[/tex] - Calorific value of the fuel, measured in kilojoules per kilogram.
[tex]Q[/tex] - Daily fuel energy, measured in kilojoules.
[tex]n[/tex] - Number of days of the month, dimensionless.
If we know that [tex]Q = 20000\,kJ[/tex], [tex]n = 30[/tex] and [tex]L_{c} = 15000\,\frac{kJ}{kg}[/tex], then the amount of fuel required to meet their energy needs for the month of April is:
[tex]m = \frac{n\cdot Q}{L_{c}}[/tex]
[tex]m = \frac{(30)\cdot (20000\,kJ)}{15000\,\frac{kJ}{kg} }[/tex]
[tex]m = 40\,kg[/tex]
40 kilograms of fuel are required to meet their energy needs for the month of April.
A student is trying to determine the density of a piece of metal. She uses a balance and finds that the mass of the piece of metal is 15.36 g. To determine the volume of the metal she fills a graduated cylinder to 30.0 mL and then drops the piece of metal into the graduated cylinder. The final volume of the metal 34.1 mL. What is the density of the piece of metal
Answer:
3.746 g/mL
Explanation:
Mass of metal = 15.36 g
Initial Volume = 30.0 mL
Final Volume = 34.1 mL
Volume of metal = Final Volume - Initial Volume = 34.1 mL - 30.0 mL
Volume of metal = 4.1 mL
Density = ?
The relationship between the values is given as;
Density = Mass of metal / Volume of metal
Inserting the values;
Density = 15.36 / 4.1 = 3.746 g/mL
The density of the piece of metal is 3.746 g/ml.
How to find the density of any metal?Given the mass of metal is 15.36 g
The initial volume of a cylinder is 30.0 ml
The final volume after putting metal in it is 34.1ml
Step 1- To find the volume:
The volume of metal = Final Volume – Initial Volume 30.0 mL
Volume of metal = 34.1 – 30.0 = 4.1 ml
Volume of metal = 4.1 mL
Step 2- Find the Density:
Density = Mass of metal is divided by the Volume of metal
[tex]\bold{Density = \dfrac{15.36 }{4.1} =3.746 g/ml}[/tex]
Thus, the density is 3.746 g/ml.
Learn more about density, here:
https://brainly.com/question/952755
What is the correct formula to determine density?
Answer:
density =mass/volume
Explanation:
p=m/v
p means raw
m means mass
v means volume.
what is the mass of 8.07 x 10^24 molecules of 02?
Answer:Avogadro's number 6.02 x 10^23 of O2 molecules has a mass of 32 gm (atomic weight of O = 16 gm, 2 x 16 = 32).
Explanation:pls brainless
Which two structures are connected by the ear bones?
eardrum and stirrup
stirrup and auditory nerve
auditory nerve and cochlea
cochlea and eardrum
Answer:
I THINK it is A
Explanation:
Answer: it is the eardrum caus ei used it on my test and as well got it right
Explanation: because it just is
[tex]hut7utpojghuire\\kjionbenhrmhbnhknokgn\\bihkjihjgnhrk\\\\gnthnrt\\hgnth\\\alpha thtrnhjn4t also this is for fun to me[/tex]