Answer:
B is correct answer because The enthalpy is negative so this means the reaction produces heat and the reaction is exothermic
N2 H4 (1) + O2
N2 (a) + 2H20()
PLEASE HELP ASAP!
How many grams of hydrazine (N2Ha) are needed to produce 52,4 g
water?
a 31.0
O b
b. 186
c. 32.0
d. 46.5
Answer:
d. 46.5 g
Explanation:
First, you need to start with a properly balanced equation:
N₂H₄(l) + 3O₂(g) -> 2NO₂(g) + 2H₂O(l)
Then, find the moles of water produced:
2H = 2.01568 amu
O = 15.999 amu
________________
18.01468 amu
52.4 g ÷ 18.01468 amu = 2.9087 moles
The mole ratio in our balanced formula between N₂H₄ : H₂O is 1 : 2, so divide moles of H₂O by 2 to get moles of N₂H₄
2.9087 moles ÷ 2 = 1.45435 moles of N₂H₄
Then, calculate the atomic mass of N₂H₄:
2N = 28.0134 amu
4H = 4.03136 amu
________________
32.04476 amu
Finally, calculate the mass in grams of N₂H₄:
1.45435 moles • 32.04476 amu = 46.604 g
Do plants need soil to grow
Answer:
Not all plants do need soil to grow
Explanation:
Not all plants need soil to grow. Some just do better in soil compared to other growing mediums. What plants need are minerals and nutrients, such as nitrogen, potassium, and phosphorous. Soil is an effective way of delivering those nutrients cost-effectively. You can also use alternative delivery systems like hydroponics, aeroponics, and aquaponics to achieve the desired effect. However, these are only suitable for growing shallow-rooted plants. Plants with deep roots will always need soil, as will larger plants with spreading roots.
What’s the name of this compound?
please answer fast............
It's O2 which is oxygen....
Answer:
c. CO2 is the answer.Explanation:
Hope this helps you. Please mark as brainliest. Good Luck^_^
Which element would have the lowest electronegativity? (1 point)
O an element with a small number of valence electrons and a small atomic radius
O an element with a small number of valence electrons and a large atomic radius
an element with a large number of valence electrons and a large atomic radius
Dan element with a large number of valence electrons and a small atomic radius
The element that will have the lowest electronegativity is an element with a small number of valence electrons and a large atomic radius.
Electronegativity of an element is the ability or power of that element in a molecule to attract electrons to its Valence electrons. The following are the properties of electronegativity:
It increases across a period from left to right of the periodic table,It decreases down the periodic table groupsGroup 1 elements are the least (lowest) electronegative elements. These elements have the lowest valence electrons with a large atomic radius. Group 7 elements are the most electronegative elements.Atomic radius of elements increase down a group because of a progressive increase in the number of shells occupied by electrons which increases the size. But it decreases across a period because electrons are accommodated within the same shell leading to greater attraction by the protons in the nucleus.
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Answer: Its B the guy above me is correct
I need help with question 2
Answer:
here's the answer to your question
How many atoms are in 1g of Hg
Answer:
7.5275 x 10^21
Explanation:
Answer:
[tex]\boxed {\boxed {\sf 3 \times 10^{21} \ atoms \ Hg}}[/tex]
Explanation:
We are asked to find how many atoms are in 1 gram of mercury.
1. Convert Grams to MolesFirst, we convert grams to moles. We use the molar mass or the mass of 1 mole of a substance. These values are equivalent to the atomic masses on the Periodic Table, but the units are grams per mole instead of atomic mass units.
Look up mercury's molar mass.
Hg: 200.59 g/molWe convert using dimensional analysis, so we create a ratio using the molar mass.
[tex]\frac { 200.59 \ g \ Hg}{ 1 \ mol \ Hg}[/tex]
We are converting 1 gram of mercury to moles, so we multiply the ratio by this value.
[tex]1 \ g \ Hg *\frac { 200.59 \ g \ Hg}{ 1 \ mol \ Hg}[/tex]
Flip the ratio so the units of grams of mercury cancel out.
[tex]1 \ g \ Hg *\frac{ 1 \ mol \ Hg} { 200.59 \ g \ Hg}[/tex]
[tex]1 *\frac{ 1 \ mol \ Hg} { 200.59}[/tex]
[tex]\frac{ 1} { 200.59} \ mol \ Hg[/tex]
[tex]0.004985293385 \ mol \ Hg[/tex]
2. Convert Moles to AtomsNext, we convert moles to atoms. We use Avogadro's Number or 6.022 × 10²³. This is the number of particles (atoms, molecules, formula units) in 1 mole of a substance. In this case, the particles are atoms of mercury.
We will use dimensional analysis and set up another ratio.
[tex]\frac {6.022 \times 10^{23} \ atoms \ Hg}{ 1 \ mol \ Hg}[/tex]
Multiply by the number of moles we calculated.
[tex]0.004985293385 \ mol \ Hg * \frac {6.022 \times 10^{23} \ atoms \ Hg}{ 1 \ mol \ Hg}[/tex]
The units of moles of mercury cancel.
[tex]0.004985293385 * \frac {6.022 \times 10^{23} \ atoms \ Hg}{ 1 }[/tex]
[tex]3.00214368 \times 10^{21} \ atoms \ Hg[/tex]
3. RoundThe original measurement of grams has 1 significant figures, so our answer must have the same. For the number we calculated, that is the ones place. The 0 in the tenths place tells us to leave the 3 in the ones place.
[tex]3 \times 10^{21} \ atoms \ Hg[/tex]
There are approximately 3×10²¹ atoms of mercury in 1 gram of mercury.
divide rs 120 I three parts which are in THE ratio of 1:2:3.
Answer:
20,40,60
Explanation:
Let the three parts be 1x, 2x and 3x
The the sum of three parts will be 1x+2x+3x = 120
6x=120
x=120/6
x=20
1x= 20x1=20
2x= 20x2=40
3x= 20x3=60
So 120 is divided in three parts that is 20,40,60
Answer From Gauth Math
Circle the correct term to complete the sentence: When you dilute a solution, the resulting solution has a concentration that is (increased/decreased) and the volume is (increased/decreased).
Answer:. The concentration is decreased and the volume is increased.
Explanation: Diluting a solution means adding more solvent, usually water, meaning that there is less solute in any sample of the solution. Adding more solvent means that the volume of the solution will increase.
When a single salt crystal is added to a cool liquid, large crystals form. Which statement about the original cool liquid is correct?
A) The liquid is a heterogeneous mixture because the crystals can be easily separated from the liquid
B) The liquid is a pure substance because it was made up of a single compound
C) The liquid is a pure substance because it was uniform before the crystal was added
D) The liquid is a homogenous mixture because the substance that formed the large crystals was uniformly dissolved
The liquid is a homogeneous mixture because the substance that formed the large crystals was uniformly dissolved.
A solution is composed of a solute and a solvent. A solution is a typical example of a homogeneous mixture.
We define a solution as any combination of solute and solvent. A solution can be regarded as a homogeneous mixture since the solute is uniformly distributed throughout the solution. The solute and solvent constitutes one phase.
When a salt crystal is added to the solution, crystallization is induced and large crystals of solute form.
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A salt crystal is a cubic form of sodium chloride that is closely bounded together by the reaction of sodium and chlorine ions during electrovalent bonding.
Taking a look at a heterogeneous mixture;
It refers to the mixtures that are not thoroughly mixed and uniform in composition.
On the other hand, homogeneous mixtures are formed when a substance i.e. solute (here, it is the salt crystal) is being added to a cool liquid(solvent) is thoroughly mixed.
From the given information, we are being told that when this single salt crystal is added to the cool liquid, large crystals are formed.
This implies that the formation of large crystals is brought about by the action of crystaliization rendering the liquid to be a homogeneous mixture.
We can therefore conclude that the correct statement about the original cool liquid is in Option D.
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If oxygen causes fire to burn, why didn't the world explode when fire burns at a particular place...since oxygen is everywhere...? Explain...
Answer:
Oxygen does not burn. It is not flammable, but it is an oxidizer.
Explanation
I think you are misunderstanding what is meant by "fire burns up air". Fire does use oxygen when it burns. But it also produces carbon dioxide. An oxygen molecule has two oxygen atoms in it. Fires use this to produce carbon dioxide by adding a single carbon atom from the fire’s fuel (wood, for instance).
hope it'll help:)
hii pls help me to balance the equation thanksss
Explanation:
2KCLO3 (s) = 2KCl (s) + 3O2 (g)
Which star has the highest surface temperature
A. blue star
B. yellow star
C. white star
D. red star
Answer:
The blue star is the hottest star.
Explanation:
Red stars are cooler than the sun, with surface temperatures of 3,500 K for a bright red star and 2,500 K for a dark red star. The hottest stars are blue, with their surface temperatures falling anywhere between 10,000 K and 50,000 K
A sample of a gas is kept at constant pressure while
its temperature is cooled from 100°C to 0°C. What
was its original volume if its final volume is 1.83 L?
Explanation:
here's the answer to your question
what is local unit?
.
Answer:
Explanation:
Local unit means a county, city, village, or township.
Read ""the Ozone Hole"" and answer the question below list at least three scientific disciplines related to chemistry mentioned or alluded to in the article
Answer:
Any 3 of the following:
atmospheric science
environmental science
climate science
biology
astronomy
human physiology and medicine
Explanation:
Got it right on edge 23
Again I am here with privious question
I have post this question last time also but no one answers. So can you solve this. I need it.
I will support your account
Answer:
The answer is below
Explanation:
1. Fractional Distillation
2. Simple Distillation
3. Filtration
4. Steam distillation or lemon grass oil extraction
plz help me with this one question
I will give u like,rate you 5 star and also follow u back.ppz help me
Answer:
Cl2(g) + H2O <–> HOCl + H+ + Cl-
Chlorine is the most popular way for the sterilization of water.
Cl2 + H2O → HOCl + HCl
is zinc a basic radical or acid radical?
Answer:
depends on the element it's reacting with..
Explanation:
if the another element requires less energy to loose electron then zinc will become negatively charged and hence becomes acidic radical..
normally if it is reacting with element with valency 4 and Atomic number less than it(Ti,Si,C) then it will lose electron and gain positive sign and henve becomes basic radical..
How many moles are in 68 liters of H2S gas at STP? :}
Answe:
Explanation:
số mol của H2S là : 68/22.4=3.03 nha
Potassium impart purple colour but beryllium do not impart any colour to the flame.Why?
Answer:
The electrons in beryllium and magnesium are too strongly bound to get excited by flame. Hence, these elements do not impart any color.A toaster has a resistance of 28 Ω and is plugged into a 110 V circuit. Using the GRASS method, what current is measured?
Answer:
The current of the toaster is 3.93A
Explanation:
Using the GRASS method:
G: Given: The information that is given is that we have 28Ω of Resistance and 110V of voltage.
R: Required: We need to find the current measured.
A: Action: We can use Ohm's law that relates resistance, voltage and current in the equation:
V = R*I
Or:
I = V/R
Where I is current in A, V is voltage = 110V and R is resistance = 28Ω
S: Solve:
I = 110V / 28Ω
I = 3.93A
S: Statement:
The current of the toaster is 3.93AConvert 16.7 inches to yards (there are 3 feet in a yard)
Using the method of dimensional analysis
Answer:
Explanation:
16.7 inches [1 foot / 12 inches] [1 yard / 3 feet] Notice how the units cancel each other out. You do have numbers in the denominator. What you get, looks like this
16.7
------
(12 * 3)
16.7 / 36
0.4639 yrds
what apparatus is used to measure small volume of liquid
Answer:
give me brainliest pls
Explanation:
Volumetric flasks
Volumetric labware is for measuring liquids with precision. Volumetric flasks, burettes, and pipettes made for measuring small amounts of liquid are the most accurate, with tolerances of less than ±0.02.
Answer:
A pipette is a laboratory instrument used to measure out or transfer small quantities of liquid, in volumes of milliliters (mL), microliters (μL).
Which of the following describes scientists?
О
A. People with only one perspective
B. People with similar personalities
C. People from different backgrounds
D. People with perfect understanding of science
What is the solubility of salt at 60°C if 2 gm of the salt is left behind when 7 gm of its saturated solution at that temperature dried?
a) 20
b) 40
c) 60
d) 80
40
Explanation:
because its Saturated
Which of the following is a scientific question you could ask about the game
of basketball?
A. Do you enjoy basketball more than volleyball?
B. Which team is this year's best?
C. Which player should be traded to another team?
D. Do teams that practice more win more games?
SUBMIT
The scientific question related to the game of basketball is option D: "Do teams that practice more win more games?"
This question is scientific because it explores a cause-and-effect relationship between practice and game outcomes. It can be investigated through empirical observation and data analysis.
To answer this question, researchers could collect data on the practice hours of different basketball teams and compare them to their corresponding game performance. Statistical analysis could be used to determine if there is a correlation between practice time and winning percentage or other performance metrics.
By examining a large sample of teams over an extended period, researchers could draw conclusions about the impact of practice on game outcomes. This scientific inquiry would contribute to the understanding of the factors that influence team success in basketball and could potentially inform training strategies and coaching techniques.
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If you start with 4.5 moles of aluminum and 6.5 moles of copper chloride to make aluminum chloride and copper, what is the limiting reagent?
2Al + 3CuCl -> 2AlCl3 + 3Cu
Answer:
The limiting reagent is CuCl
Explanation:
The initial number of moles of aluminum, Al = 4.5 moles
The number of moles of copper, Cu = 6.5 moles
The given chemical reaction is presented as follows;
2Al + 3CuCl → 2AlCl₃ + 3Cu
Therefore, we have, 2 moles of aluminum combine with 3 moles of CuCl produces 2 moles of AlCl₃ and 3 moles of Cu
1 mole of Al will combine with (3/2) moles of CuCl,
Therefore, 4.5 moles of Al will combine with (4.5 × (3/2) = 6.75) 6.75 moles of CuCl
Given that the number of moles of CuCl present is only 6.5 moles which is less than the 6.75 moles required to combine with the 4.5 moles, the 6.5 moles of CuCl limits the amount of AlCl₃ and Cu produced, and therefore the CuCl is the limiting reagent.
PLZ HELP There are two main ways that organisms reproduce, or make more Individuals of their own kind. Which of the following is true of these two types of reproduction?
A. In one way, two parents are involved. In the other, there is only one parent
B. In reproduction that involves only one parent, the offspring are different from the parent. In reproduction that involves two parents, the offspring receive exact copies of the parents' DNA.
C. In both ways, offspring share characteristics with their parents but are not exactly the same. O
D. In both ways, all offspring are identical to each other but maji different from their parents.
Answer:
A
Explanation:
Two parents are involved in Sexual Reproduction but only one is involved in Asexual Reproduction.
It is often possible to change a hydrate into an anhydrous compound by heating it to drive off the water (dehydration). A 43.19 gram sample of a hydrate of MgBr2 was heated thoroughly in a porcelain crucible, until its weight remained constant. After heating, 27.21 grams of the anhydrous compound remained. What is the formula of the hydrate?
Answer:
[tex]\rm MgBr_2 \cdot 6\, H_2O[/tex].
Explanation:
Let [tex]x[/tex] denote the number of [tex]\rm H_{2}O[/tex] formula units for every [tex]\rm MgCl_{2}[/tex] formula unit. The formula of the hydrate would be [tex]{\rm MgBr_2} \cdot x\, {\rm H_2O}[/tex].
Look up the relative atomic mass of each element on a modern periodic table:
[tex]\rm Mg[/tex]: [tex]24.305[/tex].[tex]\rm Br[/tex]: [tex]79.904[/tex].[tex]\rm H[/tex]: [tex]1.008[/tex].[tex]\rm O[/tex]: [tex]15.999[/tex].Formula mass:
[tex]\begin{aligned}M({\rm MgBr_{2}}) &= 24.305 + 2 \times 79.904 \\ &= 184.113\; \rm g\cdot mol^{-1}\end{aligned}[/tex].
[tex]\begin{aligned}M({\rm H_{2}O}) &= 2 \times 1.008 + 15.999 \\ &= 18.015\; \rm g\cdot mol^{-1}\end{aligned}[/tex].
The anhydrous compound would be [tex]\rm MgBr_{2}[/tex]. There was [tex]27.21\; \rm g[/tex] of this compound. Calculate the number of moles of formula units in that much of this compound:
[tex]\begin{aligned}n({\rm MgBr_{2}}) &= \frac{m({\rm MgBr_{2}})}{M({\rm MgBr_{2}})} \\ &= \frac{27.21\; \rm g}{184.113\; \rm g \cdot mol^{-1}} \\ &\approx 0.1478\; \rm mol\end{aligned}[/tex].
During heating, [tex]43.19\; \rm g - 27.21\; \rm g = 15.98\; \rm g[/tex] of water [tex]\rm H_{2}O[/tex] escaped from the hydrate. Calculate the number of formula units in that [tex]15.98\; \rm g[/tex] of [tex]\rm H_{2}O\![/tex]:
[tex]\begin{aligned}n({\rm H_{2}O}) &= \frac{m({\rm H_{2}O})}{M({\rm H_{2}O})} \\ &=\frac{43.19\; \rm g - 27.21\; \rm g}{18.015\; \rm g \cdot mol^{-1}} \\&= \frac{15.98\; \rm g}{18.015\; \rm g \cdot mol^{-1}} \\ &\approx 0.887\; \rm mol\end{aligned}[/tex].
In other words, approximately [tex]0.1478\; \rm mol[/tex] of [tex]\rm MgBr_{2}[/tex] formula units (and hence the same number of moles of [tex]{\rm MgBr_2} \cdot x\, {\rm H_2O}[/tex] formula units) contain approximately [tex]0.887\; \rm mol[/tex] of [tex]\rm H_{2}O[/tex] formula units. Calculate the ratio between the two:
[tex]\begin{aligned}x &= \frac{n({\rm H_{2}O})}{n({\rm MgBr_2})} \\ &\approx \frac{0.1478\; \rm mol}{0.887\; \rm mol} \approx 6\end{aligned}[/tex].
Hence, the formula of the hydrate would be [tex]\rm MgBr_2 \cdot 6\, H_2O[/tex].