Answer:
may be 700Explanation : What i feel is that the chemical formula is 2 H2 + O2 — 2 H2O
So taking 500 as 2 H2 that the value of O2 reacted will be half of original value that is 200...
True or False: Photosynthesis can take place under water.
True
False
Answer:
True
Explanation:
hope this helps mate
Verdadero o falso si un átomo presenta de 5 a 7 electrones en su nivel más extremo tenderá a perderlos?
unsa ang karaan nga duwa saonang panaho
Answer:
Ang kasaysayan ng mga laro ay nagmula sa sinaunang nakaraan ng tao. Ang mga laro ay isang mahalagang bahagi ng lahat ng mga kultura at isa sa pinakamatandang anyo ng pakikipag-ugnay sa lipunan ng tao. Ang mga laro ay gawing pormal na pagpapahayag ng paglalaro na nagpapahintulot sa mga tao na lumampas sa agarang imahinasyon at magdirekta ng pisikal na aktibidad. Kasama sa mga karaniwang tampok ng mga laro ang kawalan ng katiyakan sa kinalabasan, napagkasunduang panuntunan, kumpetisyon, magkakahiwalay na lugar at oras, mga elemento ng kathang-isip, mga elemento ng pagkakataon, iniresetang mga layunin at personal na kasiyahan.
Nakukuha ng mga laro ang mga ideya at pananaw sa mundo ng kanilang mga kultura at ipinapasa sa hinaharap na henerasyon. Ang mga laro ay mahalaga bilang mga kaganapan sa pagbubuklod ng kultura at panlipunan, bilang mga tool sa pagtuturo at bilang mga marka ng katayuan sa lipunan. Bilang pampalipas ng oras ng pagkahari at ng mga piling tao, ang ilang mga laro ay naging karaniwang tampok ng kultura ng korte at binigyan din bilang mga regalo. Ang mga larong tulad ni Senet at ang Mesoamerican ball game ay madalas na pinuno ng mitiko at ritwal na relihiyosong kahalagahan. Ang mga larong tulad ng Gyan chauper at The Mansion of Happiness ay ginamit upang magturo ng mga aralin na pang-espiritwal at etikal habang sina Shatranj at Wéiqí (Go) ay nakita bilang isang paraan upang mapaunlad ang madiskarteng pag-iisip at kasanayan sa kaisipan ng mga elite sa politika at militar.
(a) Calculate the number of electrons in a small, electrically neutral silver pin that has a mass of 7.0 g. Silver has 47 electrons per atom, and its molar mass is 107.87 g/mol.
Answer: The number of electrons in given amount of silver are [tex]1.839\times 10^{24}[/tex]
Explanation:
The number of moles is defined as the ratio of the mass of a substance to its molar mass.
The equation used is:
......(1)
We are given:
Mass of silver = 7.0 g
Molar mass of silver = 107.87 g/mol
Putting values in equation 1:
[tex]\text{Moles of silver}=\frac{7.0g}{107.87g/mol}=0.0650 mol[/tex]
According to the mole concept:
1 mole of a compound contains [tex]6.022\times 10^{23}[/tex] number of particles.
Number of electrons per atom of silver = 47
So, 0.065 moles of silver will contain = [tex](0.065\times 6.022\times 10^{23}\times 47)=1.839\times 10^{24}[/tex] number of electrons
Hence, the number of electrons in given amount of silver are [tex]1.839\times 10^{24}[/tex]
Write a balanced nuclear equation for the following: The nuclide astatine-218 undergoes alpha emission to give bismuth-214
____________ → _______ + __________
Answer:
[tex]^{218}_{85}At\rightarrow ^{214}_{83}Bi+^{4}_{2}He[/tex]
Explanation:
Hello there!
In this case, since the radioactive reaction for the alpha emission of astatine-218 to bismith-214 involve the release of a helium atom as shown below:
[tex]^{218}_{85}At\rightarrow ^{214}_{83}Bi+^{4}_{2}He[/tex]
Whereas the atomic number decreases by 2 and the mass number by 4 in agreement to the release of the Helium atom.
Regards!
What three parts of your eye work together to create a clear image?
Answer:
cornea,Jens and pupil
tma Po yan
How many grams of hydrogen gas, H, are necessary to produce 119.0 g of ammonia, NH3?
Answer:
What's the equation?
Answer:
14.5 g
Explanation:
its true
Given a mass of 70 g and a volume of 25 mL, what is the density?
Answer:
The density should be 2.8 g/mL.
Explanation:
To solve this problem, we must remember that we find density using the following formula:
Density = mass/volume
Therefore, if we plug in the values we are given in the problem, we get:
Density = 70 g / 25 mL
Density = 2.8 g/mL
Therefore, the correct answer is 2.8 g/mL.
Hope this helps!
Before the lab student needs to make necessary chemical reagent solutions, the teacher asked them to make 50.0mL of 1.0 M H2SO4 from a 6.0 M sock
V1=
M1=
V2=
M2=
Answer:
V1 = 8.3 mL
Explanation:
Step 1: Given data
Initial volume (V1): ?
Initial concentration (M1): 6.0 M
Final volume (V2): 50.0 mL
Final concentration (M2): 1.0 M
Step 2: Calculate the volume of the initial solution
We want to prepare a dilute solution from a concentrated one. We can calculate the volume of the initial solution using the dilution rule.
M1 × V1 = M2 × V2
V1 = M2 × V2 / M1
V1 = 1.0 M × 50.0 mL / 6.0 M = 8.3 mL
We will take 8.3 mL of the 6.0 M solution and add water until we have 50.0 mL.
The mass percent of element X
in X(NO3)2 is 52.55%.
Chemical analysis of a pure
sample of X(NO3)2 shows that
it contains 67.50 g of element
X. What is the total mass of
the pure sample?
Answer:
128.4 g
Explanation:
Step 1: Given data
Mass percent of element X in X(NO₃)₂: 52.55%Mass of the element X in the sample: 67.50 gStep 2: Determine the total mass of the sample
The mass percent of element X in X(NO₃)₂ is 52.55%, that is, there are 52.55 g of X every 100 g of X(NO₃)₂. Then, the mass of X(NO₃)₂ that contains 67.50 g of X is:
67.50 g X × 100 g X(NO₃)₂/52.55 g X = 128.4 g X(NO₃)₂
In the electrolysis of water, how long will it take to produce 75.00 L of H2 at 1.0 atm and 273 K using an electrolytic cell through which the current is 205.0 mA
answer is 2546 h
mark me as Branliest
Ammonia burns in the presence of a copper catalyst to form nitrogen gas. 4 NH3(g) + 3 O2(g) → 2 N2(g) + 6 H2O(g) ΔΗ = -1267 kJ What is the enthalpy change to burn 38.4 g of ammonia?
Answer:
-713 kJ
Explanation:
Step 1: Write the balaned thermochemical equation
4 NH₃(g) + 3 O₂(g) → 2 N₂(g) + 6 H₂O(g) ΔΗ = -1267 kJ
Step 2: Calculate the moles corresponding to 38.4 g of NH₃
The molar mass of NH₃ is 17.03 g/mol.
38.4 g × 1 mol/17.03 g = 2.25 mol
Step 3: Calculate the enthalpy change to burn 2.25 mol of ammonia
According to the thermochemical equation, 1267 kJ are released per 4 moles of ammonia that react.
2.25 mol × (-1267 kJ/4 mol) = -713 kJ
Americium-241 is widely used in smoke detectors. The radiation released by this element ionizes particles that are then detected by a charged-particle collector. The half-life of 241Am is 432 years, and it decays by emitting alpha particles. How many alpha particles are emitted each second by a 5.54-g sample of 241Am
Answer:
Explanation:
Half life T is 432 years .
432 years = 432 x 365 x 24 x 60 x 60 s
= 1.36 x 10¹⁰ s .
No of atoms in 5.54 g of sample of Am N= 6.02 x 10²³ x 5.54 / 241
N = 138.38 x 10²⁰ atoms .
disintegration constant λ = .693 / half life
λ = .693 / 1.36 x 10¹⁰ s .
= .51 x 10⁻¹⁰ .
dN / dt = λN
= .51 x 10⁻¹⁰ x 138.38 x 10²⁰
= 70.57 x 10¹⁰ per second.
No of particles emitted = no of disintegration per second
No of particles emitted = 70.57 x 10¹⁰ per second.
How did the development of the earliest idea about atoms differ from the later work of scientists?
It was based on sound evidence.
There were explanations for the idea.
It was based on the thoughts of an early philosopher.
There were experiments conducted to support the idea.
Answer:
C. It was based on the thoughts of an early philosopher.
What is the mass of 8.12 ×10^23
Answer:
59.3g
Explanation:
Mole = no. Molecules/6.02×10^23
Mole = (8.12×10^23)/(6.02×10^23)
Mole = 1.35mole
Molar mass of CO2 = 12+ 2(16)
Molar mass= 12 + 32= 44g/mol
Mole = mass/molar mass
Mass = Mole × molar mass
Mass = 1.35× 44
Mass= 59.35g
You are given a solution containing a pair of enantiomers (A and B). Careful measurements show that the solution contains 98% A and 2% B. What is the ee of this solution
Answer:
ee = 96%
Explanation:
Enantiomeric excess, ee, is a way to express a mixture that is not enantiomerically pure. It is defined as 100 times the ratio between the differences of amounts of enantiomers and the total amunt. that is:
ee = |A-B|/ A+B * 100
ee = |98%-2%| / 98+2 * 100
ee = 96%which of the following experiments raises ethical concerns
Answer:
Research that releases a poisonous gas into the air.
Explanation:
Since I don't know the options I will guess it is ^
Which of the following is formed last in daughter cells when plant cells divide?
The nucleus
The nuclear envelope
The cell membrane
The cell wall
Answer:
The Cell Wall
Explanation:
Naturally occurring gallium is a mixture of isotopes
that contains 90.11% of Ga-69 (atomic mass = 68.93
u) and 9.89% of Ga-71 (atomic mass 70.92 u).
What is the average atomic mass of naturally
occurring gallium?
A) 69.93 amu
C) 69.50 amu
B) 69.12 amu
D) 69.00 amu
A sample of gas starts at 1.00 atm, 0.00° C, and 30.0 mL. What is the volume if the temperature increases to 27.0° C and the pressure increases to 2.00 atm?
Answer:
16.48 mL.
Explanation:
From the question given above, the following data were obtained:
Initial pressure (P₁) = 1 atm
Initial temperature (T₁) = 0 °C
Initial volume (V₁) = 30 mL
Final temperature (T₂) = 27 ° C
Final pressure (P₂) = 2 atm
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) = 0 °C
Initial temperature (T₁) = 0 °C + 273
Initial temperature (T₁) = 273 K
Final temperature (T₂) = 27 °C
Final temperature (T₂) = 27 °C + 273
Final temperature (T₂) = 300 K
Finally, we shall determine the final volume of the gas. This can be obtained as:
Initial pressure (P₁) = 1 atm
Initial temperature (T₁) = 273 K
Initial volume (V₁) = 30 mL
Final temperature (T₂) = 300 K
Final pressure (P₂) = 2 atm
Final volume (V₂) =?
P₁V₁ / T₁ = P₂V₂ / T₂
1 × 30 / 273 = 2 × V₂ / 300
30 / 273 = 2 × V₂ / 300
Cross multiply
273 × 2 × V₂ = 30 × 300
546 × V₂ = 9000
Divide both side by 546
V₂ = 9000 / 546
V₂ = 16.48 mL
Therefore, the final volume of the gas is 16.48 mL.
What is the pH of a solution whose hydronium ion [H20+] (or proton [H+1)
concentration is 7.6' 10-5 M?
Answer:
[tex]pH = - log(7.6 \times {10}^{ - 5} ) \\ pH = 4.12[/tex]
Write the equation showing the formation of a monosubstituted product when butane reacts with chlorine. Use molecular formulas for the organic compounds (C before H, halogen last) and the smallest possible integer coefficients.
Answer:
CH3CH2CH2CH3 + Cl2 --------> CH3CH2CH2CH2Cl + HCl
Explanation:
Alkanes react with halogens in the presence of light to yield alkyl halides. The degree of substitution increases as the reaction progresses. The reaction occurs by free radical mechanism.
The reaction between butane and chlorine molecule to yields a monosubstitution product occurs as follows;
CH3CH2CH2CH3 + Cl2 --------> CH3CH2CH2CH2Cl + HCl
Completa las siguientes reacciones, nombrando todos los compuestos que intervienen:
a) CH2=CH2 + energía
b) CH2=CH2 + H2O
c) CH2=CH2 + HCl
d) CH2=CH2 + Cl2
e) CH2=CH2 + H2
2 Completa las siguientes reacciones, nombrando todos los compuestos que intervienen:
a) CH4 + Cl2
b) CH2=CH2 + H2O
c) CH≡CH + H2
d) CH3-COOH + KOH
e) CH3OH + CH3-COOH
3 Completa y ajusta la siguientes reacciones nombrando todos los compuestos que intervienen en cada una de ellas:
a) CH3-COOH + NaOH
b) CH3-CH2I + NH3
c) CH2=CH2 + H2O
d) CH3-CH=CH2 + Br2
Answer:
1
Explanation:
hhihh2
An ion has 38 protons, 36 electrons, and 40 neutrons, what us the elements symbol
The symbol of the element in which it's ion has 38 protons, 36 electrons, and 40 neutrons is ⁷⁸₃₈Sr
How do I determine the symbol of the element?To obtain the symbol of the element, we shall obtain the mass number of the element. This is shown below:
Proton = 38Neutron = 40Mass number = ?Mass number = Proton + Neutron
Mass number = 38 + 40
Mass number = 78
Finally, we shall determine the symbol of the element. Details below:
Proton = 38Atomic number (z) = Proton = 38Mass number (A) = 78Symol of element =?From the periodic table, the element with atomic number of 38 is Strontium.
Thus, the symbol of the element will be ⁷⁸₃₈Sr
Learn more about symbol:
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Which statements explain the relationship between photosynthesis and cellular respiration? Select two options.
The glucose that plants use for energy is made by animals in cellular respiration.
Glucose is a reactant in both photosynthesis and cellular respiration
The oxygen released by photosynthesis is breathed in by animals to break down glucose.
Carbon dioxide is a product of both photosynthesis and cellular respiration
The carbon dioxide released by animals is used to build glucose in photosynthesis.
Answer:
the 2nd and 5th
Explanation:
they are both correct
Answer:
b and d | Glucose is a reactant in both photosynthesis and cellular respiration. | Carbon dioxide is a product of both photosynthesis and cellular respiration.
Explanation:
hope this helps.
What word means the same as Chordata?
A. non-vertebrate
B. vertebrate
How many molecules are there in 4.27 mol of tungsten(VI) oxide, WO3
Answer:
Molar mass of WO3 = 231.8382 g/mol Convert grams Tungsten(VI) Oxide to moles or moles Tungsten(VI) Oxide to grams Molecular weight calculation: 183.84 + 15.9994*3Explanation:
#hopeithelpsbrainliest me later.25.71 × 10²³ molecules are there in 4.27 mol of tungsten (VI) oxide, [tex]WO_3[/tex].
How to find the number of molecules ?To find the Number of molecules of substance multiply the number of moles of given substance by Avogadro number
Number of molecules = Number of moles × Avogadro's Number
Avogadro's NumberAvogadro's number [tex](N_{A})[/tex] is the number of particles in one mole of substance. 6.023 × 10²³ is known as Avogadro's constant / Avogadro's number.
Avogadro's number = 6.023 × 10²³ [tex]mol^{-}[/tex]
Now,
Number of molecules in 4.27 moles of [tex]WO_{3}[/tex]
= Number of moles of [tex]WO_{3}[/tex] × Avogadro's Number
= 4.27 × 6.023 × 10²³
= 25.71 × 10²³ molecules
Thus, we can say that 25.71 × 10²³ molecules are there in 4.27 moles of tungsten (VI) oxide, [tex]WO_3[/tex].
Learn more about the Avogadro's Number here: https://brainly.com/question/859564
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Chromium (VI) forms two different oxyanions, the orange dichromate ion, Cr2o72-, And the yellow chromate ion, CrO4 2-. The equilibrium reaction between the ions is:
Cr2O7 2- (aq) + H2O(l)→ 2CrO4 2-(aq) + 2H(aq)
Explain
a) Why does the orange dichromate solution turn yellow when sodium hydroxide is added. Write the net ionic equation for this shift.
b) How will this system shift at equilibrium if the temperature is increased
Answer:
See explanation
Explanation:
Let us look at the reaction again;
Cr2O7 2- (aq) + H2O(l)⇄ 2CrO4 2-(aq) + 2H^+(aq)
When we add sodium hydroxide to the system as shown, the hydroxide ion removes the hydrogen ion thereby leaving a large concentration CrO4^2-(aq) in the system this causes the solution to turn green(equilibrium position shifts to the right).
The net ionic equation is;
OH^-(aq) + H^+(aq) ----> H2O(l)
The reaction;
OH^-(aq) + H^+(aq) ----> H2O(l) is exothermic hence, if the temperature of the system is increased, the equilibrium position will shift towards the left hand side and the solution turns orange.
Which term describes matter that can vary in composition?
Answer:
A mixture is matter that can vary in composition. ... A heterogeneous mixture is a type of mixture in which the individual substances are not evenly mixed. Because the substances in a heterogeneous mixture are not evenly mixed, two samples of the same mixture can have different amounts of the substance.
Explanation:
Given the Vapour Density of a hydrocarbon is 150, what is it's molecular formula.
