Answer:
B) Na3BO3.
Explanation:
Hello!
In this case, since percent compositions are used to identify the empirical formula of an unknown compound, we can assume we have 54.0 g of sodium, 8.50 g of boron and 37.5 g of oxygen, and we compute the moles of each one:
[tex]n_{Na}=54.0g*\frac{1mol}{23g} =2.35mol\\\\n_B=8.50g*\frac{1mol}{11g}=0.773mol\\\\n_O=37.5g*\frac{1mol}{16g}=2.34mol[/tex]
Now, we divide by the moles of boron as those are the fewest:
[tex]Na:\frac{2.35}{0.773}=3\\\\B:\frac{0.773}{0.773}=1\\\\O=\frac{2.34}{0.773}=3[/tex]
Thus, the empirical formula is B) Na3BO3.
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Trees often lose their leaves in the winter. Explain what this tree will not be able to do without its leaves.
Answer:
Most aren't able to take in carbon dioxide gas from the air or produce any oxygen.
Explanation:
science bro
what is meant by the term quantitative?
A) number measurement
B) words & explanation
Answer:
a) number measurement
Explanation:
relating to, measuring, or measured by the quantity of something rather than its quality.
Answer:
number and measurement
Explanation:
Quantitative is an adjective that simply means something that can be measured. For example, we can count the number of sheep on a farm or measure the gallons of milk produced by a cow.
What is the volume of 100 g neon at STP?
Answer:
Well
STP
specifies 100⋅kPa,and 273.15⋅K...
Explanation:
And so we solve for n
moles of gas
in the Ideal Gas equation, and of course we have to fish out an appropriate gas constant...
n=PVRT=100⋅kPa×10⋅L8.314⋅L⋅kPa⋅K−1⋅mol−1×273.15⋅K
=0.440⋅mol
And thus a mass of 0.440⋅mol×20.18⋅g⋅mol−1...approx. 9⋅g...
Explanation:
How many known elements have atoms, in their ground-state, with valence electrons whose quantum numbers are n = 5 and l = 1?a. 36..
b. 37.
c. 6.
d. 8.
Answer:
c. 6.
Explanation:
Looking at the description given in the question, the elements involved must belong to the p- block of the periodic table and must be in period 5. They also must possess valence electrons in the 5p- orbital.
Now if we look at the p- block of period 5, the following elements satisfy these requirements; Sr, In, Sn, Sb, Te and I.
Hence there are six of such elements.
The chemical elements that have atoms, in their ground-state, with valence electrons whose quantum numbers are n = 5 and l = 1 are: C. 6.
What is a valence electron?A valence electron can be defined as the number of electrons that is present in the outermost shell of an atom.
In Chemistry, valence electrons are primarily used to determine whether an atom or group of chemical elements that are found on the periodic table can bond with others.
Based on electronic configuration, quantum numbers of n = 5 and l = 1 simply represents a 6p orbital and there a total of six (6) chemical elements with this orbital, and these include;
ThalliumLeadRadonAstatinePoloniumBismuthRead more on valence electrons here: https://brainly.com/question/16554158
In a chemical formula or a chemical equation, what is the small number after the element symbol?
Answer:
It's called a subscript.
Explanation:
Subscripts tell you how many atoms of an element are in a compound.
Your aunt is sipping on iced tea and fanning herself during a hot South Carolina summer day. You tell her that there is enough energy in one drop of her iced tea to run the air conditioner for the rest of her life if the energy could be extracted with 100% efficiency. Your aunt asks you to explain. Use the concepts you learned in this unit to explain the relationship between forces, energy, and matter.
Answer:
Isn't this like having enough energy to supply the world for centuries with just 1% of the sea's force?
Explanation:
I guess it's because the amount of energy in it can supply energy.
why are there different types of matter.
Answer:
solid ; liquid and gas........
Draw the Lewis structure for the polyatomic amide anion(NH2-). Be sure to include all resonance structures that satisfy the octet rule.
Answer:
Following are the solution to this question:
Explanation:
Following are the lewis structure of the [tex]NH_2^{-}[/tex]:
In the given element two H and one N are used, in which N has 5 valance electrons, and one H has 1 valence which is equal to 2 electrons valance. So, the graph for the given element is defined in the attached file.
The Lewis structure for the amide anion can be shown as in the given figure.
What is Lewis structure?
Lewis structures, also known as Lewis dot formulas, are diagrams that show the bonding between atoms of a molecule, as well as the lone pairs of electrons that may exist in the molecule.
In the given element two H and one N are used, in which N has 5 valance electrons, and one H has 1 valence which is equal to 2 electrons valance. The Lewis structure for the amide anion can be shown
Hence, this is the required answer.
To learn more about Lewis structures, click here:
https://brainly.com/question/4144781
how must carbon and vanadium combine to form a metallic compound?
Answer:
In general, metal and nonmetals combine to form ionic compounds
Explanation:
In the reaction of aluminum with iron III oxide, if you start with 54.2 grams of aluminum, how many grams of iron III oxide are needed for the reaction to occur?
Answer:
[tex]m_{Fe_2O_3}=160.41gFe_2O_3[/tex]
Explanation:
Hello!
In this case, since the reaction between aluminum and iron (III) oxide is:
[tex]2Al+Fe_2O_3\rightarrow Al_2O_3+2Fe[/tex]
In such way, since there is 2:1 mole ratio between aluminum (atomic mass = 26.98 g/mol) and iron (III) oxide (molar mass = 159.70 g/mol), we'll be able to compute the mass of the required reactant as shown below:
[tex]m_{Fe_2O_3}=54.2gAl*\frac{1molAl}{26.98gAl}* \frac{1molFe_2O_3}{2molAl}*\frac{159.70gFe_2O_3}{1molFe_2O_3}\\\\m_{Fe_2O_3}=160.41gFe_2O_3[/tex]
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need help asap........................................
Answer:
its a
Explanation:
beacause the movement goes forward
In the case of a rigid rorator, i.e. two masses M1 and M2 placed on a rigid weightless rod, we start from the Schrodinger equation for two particles 1 and 2, and then we separate the movement of the center of masses. Give the formulas of both masses that we get as part of this procedure. Calculate these masses in atomic mass units for the HD molecule by approximating the masses H and D with their mass numbers.
Answer:
Masses in atomic mass units for the HD molecule by approximating the masses H and D with their mass numbers is explained below in complete detail.
Explanation:
Two volumes M1 and M2 are located on a rigid weightless rod in a rigid rotor position. Energy in a rigid rotator example: E = BJ(J+1) where, B = h/8pi2Ic, B is rotational regular, I is moment of inertia = ur2 where u is decreased mass = m1m2/m1+m2.
FOR HD MOLECULE: mass, u = mass of H*mass of D/mass of H + D. Atomic mass unit =1.67*10^-27 kg. So, u = 1*1.67*10-24 * 2*1.67*10-24 / 1.67*10-24+2*1.67*10-24 = 1.67*10-24*2/3 = 1.11*10-24 g.
At room temperature, one of the molecules is a gas and one is a liquid. Identify which structure is a gas and which is a liquid.
According to the CDC, influenza is a respiratory illness caused by the flu virus. Some of the symptoms include cough, sore throat, muscle aches, and vomiting.
Which statement represents a reasonable claim about the effects of the flu virus on the body’s ability to maintain homeostasis?
A
Influenza affects one major system, which must work to restore homeostasis.
B
Influenza affects one system, but multiple systems must interact in order to restore homeostasis.
C
Influenza affects multiple systems and multiple systems must interact in order to restore homeostasis.
D
Influenza affects one major system and secondary systems, but the major system works to restore homeostasis.
Answer:
B. Influenza affects one system, but multiple systems must interact in order to restore homeostasis.
Explanation:
According to the CDC, influenza is a respiratory illness caused by the flu virus of which some symptoms include cough, sore throat, muscle aches, and vomiting.
The statement that represents a reasonable claim about the effects of the flu virus on the body’s ability to maintain homeostasis is that it affects one system which is the RESPIRATORY SYSTEM but multiple systems must intervene in other to maintain homeostatis.
*Homeostatis is the unique way a human body or organism stabilises its internal state despite the changes on the external.
What is the electron configuration of chlorine (CI)?
A. 1s22s22p63s23p3
B. 1s22s22p63s23p5
C. 1s22s22p63s24s23p3
D. 1s22s22p63s23p23d3
The correct answer is B on edg 2020
Answer: it is b
Explanation:
What gives yeast cells what it needed to reproduce and grow?
Answer:
Yeasts reproduce asexually by a process called budding (see Figure 8.2. 1 and Figure 8.2. 6). A bud is formed on the outer surface of the parent cell as the nucleus divides.
Explanation:
what's element on the periodic table has the symbol w
Answer:
W is tungsten on the periodic table
Answer the in under 30 minutes and I will give brainliest
After which event in Indonesia did one of the worst tsunamis form?
a hurricane
a volcanic eruption
a landslide
an earthquake
Answer: I believe the answer is an earthquake.
Explanation: Sorry If I am wrong!
Answer:
earthquake
Explanation:
I took the k12 test
What is the name of the "invisible force" that holds you to Earth's surface
Answer:
Gravity
Explanation:
Answer: gravity
Explanation: gravity has is an “invisible force” that holds matter down instead of floating off into space.
Can a trout and a catfish be members of the same population?
Answer:
Most likely. They eat different prey items so they would use niche partitioning. for example the leopards and lions of africa. They are both large carnivores, but are able to coexist by evolving to prey on different animals.
Explanation:
A 0.98 gram sample of a volatile liquid was heated to 348 k. the gas occupied 265 ml of space at a pressure of 0.95 atm. what is the molecular weight of this gas?
Answer:
The molecular weight is [tex]Z = 111.2 \ g/mol[/tex]
Explanation:
From the question we are told that
The mass of the sample is [tex]m = 0.98 \ g[/tex]
The temperature is [tex]T = 348 K[/tex]
The volume which the gas occupied is [tex]V = 265 \ ml = 265 *10^{-3} L[/tex]
The pressure is [tex]P = 0.95 \ atm[/tex]
Generally from the ideal gas equation we have that
[tex]PV = n RT[/tex]
Here n is the number of moles of the gas while the R is the gas constant with value [tex]R = 0.0821 \ atm \cdot L \cdot mol^{-1} \cdot K^{-1}[/tex]
[tex]n = \frac{PV}{ RT}[/tex]
=> [tex]n = \frac{ 0.95 * 265 *10^{-3} }{ 0.0821 * 348}[/tex]
=> [tex]n = 0.00881 \ mol[/tex]
Generally the molecular weight is mathematically represented as
[tex]Z = \frac{m}{n}[/tex]
=> [tex]Z = \frac{0.98 }{0.00881}[/tex]
=> [tex]Z = 111.2 \ g/mol[/tex]
Carbon-14, which is present in all living tissue, radioactively decays via a first-order process. A one-gram sample of wood taken from a living tree gives a rate for carbon-14 decay of 13.6 counts per minute. If the half-life for carbon-14 is 5720 years, how old is a wood sample that gives a rate for carbon-14 decay of 7.9 counts per minute?
A. 5.3 x 102 yr.B. 7.6 x 102 yr.C. 1.1 x 103 yr.D. 9.5 x 103 yr.
The question is incorrect, the correct question is;
Carbon-14, which is present in all living tissue, radioactively decays via a first-order process. A one-gram sample of wood taken from a living tree gives a rate for carbon-14 decay of 13.6 counts per minute. If the half-life for carbon-14 is 5720 years, how old is a wood sample that gives a rate for carbon-14 decay of 11.9 counts per minute?
Answer:
C. 1.1 x 103 yr
Explanation:
A = count rate of the wood sample
Ao= count rate of a living tissue
t1/2= half life of C-14
t = time taken
From;
0.693/t1/2 = 2.303/t log Ao/A
0.693/5720 = 2.303/t log (13.6/11.9)
1.2 * 10^-4 = 2.303/t * 0.05799
1.2 * 10^-4 = 0.1336/t
t = 0.1336/1.2 * 10^-4
t = 1.1 x 103 yr
if you have 4 moles of n2 and 6 moles of h2, how much would be produced?
Answer:
8 i think
Explanation:
A motorist discovers that her auto tire measures 29.2 psi rather than the recommended 35 psi. If the tire’s volume is assumed constant at 11.6 L and the temperature is 45F at the filling station, how many moles of air will the motorist need to add to bring the tire to 35 psi? (assume 1.00 atm = 14.7 psi)
Answer:
0.20 moles
Explanation:
The pressure is proportional to the quantity of gas at a given temperature and volume. So, the quantity needs to be increased by a factor of ...
(35 psi)/(29.2 psi) = 175/146 ≈ 1.19863
The fractional increase required is ...
1.19863 -1 = 0.19863
__
The quantity of air currently in the tire is ...
1 mol·519.67°R/(atm·23.6442 L) × (29.2/14.7 atm) × (11.6 L) / (45+459.67)°R
= 1.0035 mol
so we need to add ...
(fraction to add) × (current quantity) = amount to add
0.19863 × 1.0035 mol = 0.1993 mol = amount to add
About 0.20 moles of air must be added to the tire to bring the pressure up.
How many protons and electrons does 8 -2 ion contain
Answer:
8 protons, 10 electrons.
Explanation:
the -2 charge adds 2 electrons–hence, you have 10 electrons while protons remain at 8.
What is the net ionic equation of Nat + OH + H+ + Cl → H20 + Na+ + Cl?
A. NaOH(aq) + HCl(aq) → H20() + NaCl(aq)
B. Na+ + Cl" > Naci
C. Na+ + OH + H+ + Cl → H+ + OH' + Na+ Cl"
O D. OH + H+ → H20
Answer:
D. OH⁻ + H⁺ → H2O.
Explanation:
Hello!
In this case, since this problem provides the complete ionic equation by which the neutralization reaction between sodium hydroxide and sodium chloride is carried out:
[tex]Na^+(aq)+OH^-(aq)+H^+(aq)+Cl^-(aq)\rightarrow Na^+(aq)+Cl^+(aq)+H_2O(l)[/tex]
Thus, since sodium and chloride ions are the spectator ones, as they are at both reactants and products, they can be cancelled out to obtain the net ionic equation as shown below:
[tex]OH^-(aq)+H^+(aq)\rightarrow H_2O(l)[/tex]
Therefore, the answer would be D. OH⁻ + H⁺ → H2O.
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PLEASE HELP MEEEE! WILL MARK BRAINLIEST IF CORRECT!
Answer:
the answer is A
Nick needs 3.5 moles of sodium fluoride (NaF) for a solution he is mixing in the lab. How many grams of NaF does Nick need to measure out?
Answer:
147 g
Explanation:
The number of moles of a substance is the ratio of the mass of the substance and the molar mass of that substance. Mathematically,
mole = mass of substance/molar mass
In this case, Nick needs 3.5 moles of NaF, the molar mass of NaF is calculated as:
23 + 19 = 42 g/mol (Note: Na = 23, F = 19)
Hence,
mass of 3.5 mole NaF = mole x molar mass
= 3.5 x 42 = 147 g.
Hence, Nick would need to measure out 147 g NaF using a suitable weighing balance.
How do substances and mixtures diifer
The composition of one is always the same, and the composition of the other varies
One contains only one type of atom, and the other contains two or more
One is always homogeneous, and the other is always heterogeneous
One contains one type of molecule, and the other contains two types
it for 100 points please give it correctly.
Answer:
hello hope this helps :)
a pure substance consists only of one element or one compound. a mixture consists of two or more different substances, not chemically joined together.
Explanation:
using the ideal gas law, PV=nRT, where R=0.0821 L atm/mol K, calculate the volume in liters of oxygen produced by the catalytic decomposition of 25.5 g potassium chlorate according to the following reaction. The oxygen is collected at 2.22 atm and 25.44 C. express your answer to the correct number of significant figures.
2KClO3(s) ---> 2KCl(s) + 3O2(g)
Answer:
V = 2.32 Liters
Explanation:
PV = nRT => V = nRT/P
n = 25.8g/122g/mole = 0.21 mole
R = 0.08206 L·atm/mol·K
T = 25.44°C + 273 = 298.44K
P = 2.22 atm (given in problem)
V = (0.21mol)(0.08206 L·atm/mol·K)(298.44K)/(2.22atm) = 2.32 Liters at 25.44°C & 2.22atm