help please i am confused
It is pholem or phloem
Answer:
phloem I believe
Explanation:
dictionary
A pupil has drawn the electronic structure of fluorine and the diagram is shown below. However,
mistakes have been made. State three mistakes that have been made.
Fl atomic number: 9
Fl atomic mass: 10
(ps i have two of these but can’t figure out the last)
Answer:
The number of electrons in the orbit is wrong they have to be 9 and not 10since flourine is in group 7 the number of electrons in the outer most shell has to be 7 and not 2the first shell has 8 instead of 2 electronsI hope this helps
What happens if kinetic energy of a gas is lowered
Answer:
"If you lower the kinetic energy of a gas its temperature will decrease because temperature is a measure of the average kinetic energy of a substance."
Explanation:
Calculate the volume (in L) that 3.25 mol of helium gas will occupy at a temperature of 25.0 °C and a pressure of 799 mm Hg.
Answer:
V = 6.34 L
Explanation:
Given that,
Number of moles of Helium gas, n = 3.25 mol
Temperature, T = 25 °C = 298 K
Pressure, P = 799 mm Hg
We know that,
PV = nRT
Where
R is the gas constant, R = 62.4 L-mm Hg/mol K
So,
[tex]V=\dfrac{nRT}{P}\\\\V=\dfrac{3.25\times 62.4\times 25}{799}\\\\V=6.34\ L[/tex]
So, the volume of the gas is 6.34 L.
Over a period of 2 minutes, 180 coulombs of charge pass through a resistor. What is the current through the resistor during this time?
Type the correct answer in the box. Use numerals instead of words.
The current through the resistor during this time is
A.
Answer:
Explanation:
Formula
The current = charge / time
The charge is in coulombs
The time has to be in seconds.
1 minute = 60 seconds
2 minutes = 120 seconds.
charge = 180 coulombs
current = 180 / 120
current = 1.5 amperes.
For a reaction: aA → Products, [A]o -4.3 M, and the first two half-lives are 56 and 28 minutes, respectively. Calculate k (without units). Show Work!
A. 7.7 x 10^-2
B. 4.2 x 10^-3
C. 3.8 x 10^-2
D. 8.3 x 10^-3
E. None of these
Answer:
C.[tex]3.8\times 10^{-2}[/tex]
Explanation:
We are given that
Initial concentration, [tex][A]_o=4.3 M[/tex]
First half life, [tex]t_{\frac{1}{2}}=56[/tex]minutes
Second half life, [tex]t'_{\frac{1}{2}}=28[/tex]minutes
We have to find K.
The given reaction is zero order reaction.
We know that for zero order reaction
[tex]t_{\frac{1}{2}}=\frac{[A]_o}{2k}[/tex]
Using the formula
[tex]56=\frac{4.3}{2k}[/tex]
[tex]k=\frac{4.3}{2\times 56}[/tex]
[tex]k=3.8\times 10^{-2}[/tex]
Hence, option C is correct.
Zero-order reactions are the reactions when a surface or a catalyst is required for the reaction to proceed and is saturated by the reactant chemicals. The result of the concentration versus the time plot will be a straight line in a zero-order reaction.
[tex]3.8 \times 10 ^{-2}[/tex] is the value of k.
How to calculate the value of k?Given,
Initial concentration [tex][A_{0}][/tex] = 4.3 MThe first half-life of the reactant [tex](t \dfrac{1}{2})[/tex] = 56 minutesThe second half-life of the reactant [tex](t \dfrac{1}{2})[/tex] = 28 minutesThe given reaction in the question is of zero-order and for that, we know that,
[tex]t \dfrac{1}{2} = \dfrac{[A_{0}] }{2\;\rm k}[/tex]
Substituting the values in the equation we get:
[tex]\begin{aligned}56 &= \dfrac{4.3 }{2\; \rm k}\\\\\rm k &= {4.3 }{2 \times 56}\\\\\rm k &= 3.8 \times 10^{ -2}\end{aligned}[/tex]
Therefore, option C is correct.
Learn more about the zero-order reaction here:
https://brainly.com/question/4638382
How are the vapor pressure and boiling point of alkynes affected as the chain length increases?
Answer:
Answer to the following question is as follows;
Explanation:
Alkynes' vapour pressure and normal boiling points are altered when chain length grows, since vapour pressure rises while boiling point falls.
Vapour pressure always include pressure entered by vapour with its condensed phase, pressure include molecules force of attraction include vapour
La masa de una olla es de 300g y contiene 90% de aluminio. Hallar el número de moles de aluminio de la olla. P.A.(Al= 27)
Explanation:
The mass of a pot is 300g and contains 90% aluminum. Find the number of moles of aluminum in the pot. P.A. (Al = 27)
The mass of aluminum present in the pot is:
[tex]300 g * 90/100\\=270 g[/tex]
Hence, in the given pot 270g Al is present.
[tex]Number of moles of Al=\frac{given mass ofAl}{its molar mass}[/tex]
The gram atomic mass of Al -27 g/mol
Given the mass of Al is 270 g
Substitute these values in the above formula:
[tex]Number of moles of Al=\frac{given mass ofAl}{its molar mass}\\=\frac{270 g}{27 g} \\=10.0 mol[/tex]
Answer is 10.0 mol of Al is present.
CORRECT ANSWER ONLY ND WILL GIVE BRAINLIEST✌
Calculate the mass of nitrogen dioxide gas that would occupy
the same volume as 10g of hydrogen gas at ē same pressure and temperature
(H= 1.0 N = 14.0 O= 16.0) GAS LAWS/MOLES
Answer:
150g
Explanation:
Assuming they are ideal gases at the same temperature and pressure, equal moles of gasses have equal volume. IN this case, if we have 10g of hydrogen gas, that is 5 moles of H2 gas. That means 5 moles og NO2 will occupy the same volume which is 5*(14.0 + 16.0*2) = 230 g
If an atom contains more
electrons than protons, it is
Answer:
If an atom has the same number of electrons as protons, it is a neutral atom.
Explanation:
Which is a mixture?
Sodium metal
chlonne gas
sodium metal and chlonne gas
sodium chlonde (salt) and water
Answer:
I believe it's salt and water
Explanation:
not sure
Answer:
Mixture is a electronic device used to peel the things such as onion ,tomato,ginger, garlic etc.
. The Ksp of barium sulfate is 1.1 × 10–10. What is the sulfate-ion concentration of a 1.0-L saturated solution of BaSO4 to which 0.025 mol of Ba(NO3)2 is added? 4.4 × 10–9M 1.0 × 10–5M 6.6 × 10–5M 2.8 × 10–12M
Answer:
[tex][SO_4^{2-}]=4.4*10^{-9}M[/tex]
Explanation:
From the question we are told that:
[tex]Ksp=1.1*10^{-10}[/tex]
Volume of [tex]SO_4^{2-}=1.O[/tex]
Moles of [tex]Ba(NO_3)^2 =0.025[/tex]
Generally the equation for Ksp is mathematically given by
[tex]Ksp=[Ba^{2+}][SO_4^{2-}][/tex]
[tex]1.1*10^{-10}=[0.025][SO_4^{2-}][/tex]
Therefore
[tex][SO_4^{2-}]=4.4*10^{-9}M[/tex]
Which element has 2 valence electrons in the 2s sublevel?
Answer:
beryllium is the answer.
I hope this will help you
when carbon is heated in a limited supply of oxygen, a gas is obtained.
1 .what is the name of this gas
Answer:
carbon monoxide
I think its correct but I am not sure
Answer: when carbon is heated in air carbon dioxide is formed, so is incomplete combustion which results in carbon monoxide.
Explanation: but when carbon dioxide reacts with more oxygen carbon monoxide is formed i guess.
I AM A BIT SURE BUT HOPE THIS HELPSSSS!!!!
______ exhibits the highest
intermolecular forces of the states of matter.
A. Solid
B. Liquid
C. Gas
D. Vacuum

QUICK CHECK
Use the periodic table to select which type of bond is present and which of the listed properties is most
likely for each substance.
Substance
Type of bond
Likely property
A А
B
A
Cuzm
Ba
lonic
DO
covalent
02
С
D
metallic
Answer:
Coppell zinc,ironic bond
Explanation:
lt will give away two zinc atoms
Answer:
I will go with Sodium chlorine NaCl
HELP ME PLZ Which of the following describes the structure of a fish's swim bladder?
A. Expands and contracts to allow the fish to rise or sink in the water
B. Internal organ filled with liquid
c. Holds urine until it can be released into the environment
D. Internal organ filled with air sacs
To begin the experiment, Xavier washed his hands and put on safety goggles. He then measured 120 milliliters of tap water, 2.5 milliliters of baking soda, and 2.5 milliliters of citric acid. The initial temperature of the water was 23.5°C.
Next Xavier added the baking soda and citric acid to the water. The mixture immediately began to bubble vigorously, which lasted for about 30 seconds. The new temperature of the mixture was 17.7°C.
Is a chemical reaction taking place during Xavier’s experiment? How do you know?
WILL GIVE BRAINLIEST!!!!!!!!!!!!!!!
Answer:
Yes a chemical reaction is taking place.
Explanation:
There is a change in temperature along with bubbling. All signs of a chemical reaction.
What is the percent yield of a reaction?
O A. The difference between measured and calculated amounts
OB.
The amount of produd obtained
amount possible
* 100
C. The amount of product actually obtained in a reaction
D. The amount of product that is possible from a reaction
Answer:
B. The amount of produd obtained/amount possible * 100
Explanation:
In chemistry, the yield of a chemical reaction is the quantity or amount of products obtained in that chemical reaction. It is calculated by using the following formula:
Percentage yield = Actual yield/theoretical yield × 100
- The actual yield is the amount of products got from a chemical reaction
- The theoretical yield is the amount of product got from using the balanced equation (stoichiometry).
What is the name of the molecule shown below?
A) ethanol
B) ethanal
C) ethanoic acid
D) ethylamine
The name of the molecule shown is Ethanol.
What is Ethanol?Ethanol is a alcoholic substance that is formed from fermentation of glucose in the presence of yeast or microorganisms.
It has a chemical group that have methyl group, hydroxyl group OH which is bonded to carbon atom.
Therefore, The name of the molecule shown is Ethanol.
Learn more about ethanol below.
https://brainly.com/question/13423304
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how much energy is required to melt 2kg of aluminium
Is this population more likely to grows slowly or quickly in the next 10 years
nobody can say it is uncertain but in my opinion it will grow quickly in the next 10 years
True or false, The universal gas constant, R, is . 0821 when we use mm Hg as our unit for pressure
Answer:
False
Explanation:
R = gas constant = 0.0821 atm•L/mol•K
Hiii pls help me to write out the ionic equation
Answer:
STEP I
This is the balanced equation for the given reaction:-
[tex] 2KOH_{(aq)} + H_2SO_4{}_{(aq)} \rightarrow K_2SO_4{}_{(aq)} + 2H_2O_{(l)} [/tex]
STEP II
The compounds marked with (aq) are soluble ionic compounds. They must be
broken into their respective ions.
see, in the equation KOH, H2SO4, and K2SO4 are marked with (aq).
On breaking them into their respective ions :-
2KOH -> 2K+ + 2OH-H2SO4 -> 2H+ + (SO4)2-K2SO4 -> 2K+ + (SO4)2-STEP III
Rewriting these in the form of equation
[tex] \underline{\pmb{2K^+} }+ 2OH^- + 2H^+ + \pmb{\underline{{SO_4{}^{2-}}} \: \rightarrow \: \underline{\pmb{2K^+}}} + \underline{\pmb{SO_4{}^{2-}}} + 2H_2O [/tex]
STEP IV
Canceling spectator ions, the ions that appear the same on either side of the equation
(note: in the above step the ions in bold have gotten canceled.)
[tex] \boxed{ \mathfrak{ \red{ 2OH^-{}_{(aq)} + 2H^+{(aq.)} \rightarrow H_2O{}_{(l)}}}} [/tex]
This is the net ionic equation.
____________________________
[tex] \\ [/tex]
[tex]\mathfrak{\underline{\green{ Why\: KOH \:has\: been\: taken\: as\: aqueous ?}}} [/tex]
KOH has been taken as aqueous because the question informs us that we have a solution of KOH. by solution it means that KOH has been dissolved in water before use.[Alkali metal hydroxides are the only halides soluble in water ]
Which is another word for 10 meters in the metric system?
Answer:
Dekameter
Explanation:
Based on the Lewis/electron dot representation
of the two atoms, predict the ratio of metal
cationic (+) atom to nonmetal anionic (-) atom in
the compound.
.Ca.
.P.
A. 1:1
B. 3:2
C. 2:1
D. 3:1
Can someone plz tell me how to do this.
Answer:
B or C think so
plz answer (g) i will give rating 5 and thanks who answer plz fast
Answer:
Like many common group 2 metal carbonates, magnesium carbonate reacts with aqueous acids to release carbon dioxide and water
MgCO3 + 2 HCl → MgCl2 + CO2 + H2O.
The procedure to obtain pure magnesium chloride from the reaction is as thus
Step 1: Reaction
- Leave the dilute hydrochloric acid in a beaker.
- Add Magnesium carbonate slowly until it is in excess or until no more gas seem to be getting liberated.
Step 2: Filtration
- Filter with filter paper and funnel.
- Filter off the excess magnesium carbonate as magnesium chloride will be in aqueous form (liquid) and will come out with the filtrate. The residue is the excess magnesium carbonate.
Step 3: Crystallization to obtain solid crystals from the filtrate.
- Pour filtrate solution into evaporating dish/basin
- Provide heat using Bunsen burner
- Pour solution into an evaporating basin and heat over a water bath
- Stop heating when crystals start to form
allow water to evaporate until pure crystals remain.
- Dry crystals using absorbent paper or warm oven.
Precautions
- Use personal protective equipment such as gloves, a lab coat and wear eye protection, especially when heating.
- Avoid inhaling unnecessary gases during the whole process.
Is FeS iron (ll) sulfide or iron (lll) sulfide?
Answer:
the valence of S is -2. For FeS to be neutral the valence of Fe used must be +2
and since Iron (II) has its valency 2, FeS will be Iron (II) Sulfide.
what is the molarity of HCL solution that has a density of 1.17g/ml at 25°?
Here, we have been given that;
$ \bf{1 ml}$ = 1.17 g$ \bf{1 l}$ = 1170 gHence, we can note that,
No. of moles of HCL (n) = $ \sf{\frac{1170}{36.5}}$(n) = 32.05
[tex] \\ [/tex]
Thus,
Molarity = 32.05 mg/LHence, molarity of the given solution will be 32.05 mg/L.
Which pair of substances would react the
fastest?
a. Copper sheet and concentrated
nitric acid.
b. Copper powder and dilute nitric acid
C. Copper powder and concentrated
nitric acid.
Answer:
C. It has the highest rate of reaction. Copper has the highest TSA/V and concentrated nitric acid has huggest num of solute
