Answer:
Explanation:
c it’s see it
Help it’s about Binary compounds and transition metals
Answer:
Cr 6+ & SO4 2-
Explanation:
Sulfate is a polyatomic ion that has a charge of 2-. There are three of them in the chemical formula so it equates to a 6- total charge. Thus, chromium must have a 6+ charge to give the compound a neutral charge.
Lab: Enthalpy.
What were the learning goals of this lab experiment? Check all that apply.
to use mass and temperature data to do computations involving heat
to demonstrate that different reactions have different enthalpies
to compute a reaction’s enthalpy directly using mass measurements and a calorimeter
to compute the enthalpy of a reaction that cannot be measured directly using a simple calorimeter
Hess
’s law allows you to find the net enthalpy of the magnesium combustion by adding the enthalpies of intermediate reactions.
To find the enthalpy of a reaction in the lab, you measured the
mass
of the reactants
and the
temperature
change during the reaction.
In both Reactions 1 and 2, the temperature change was
positive
, meaning that the
reactions
gave off
heat.
Answer:
to use mass and temperature data to do computations involving heat
to compute a reaction’s enthalpy directly using mass measurements and a calorimeter
To find the enthalpy of a reaction in the lab, you measured the mass
of the reactants
and the
temperature
change during the reaction.
Explanation:
Was that good?
Enthalpy is a thermodynamic system's internal energy total as well as the volume times pressure ratio.
What is Enthalpy?Enthalpy is a property or state function that resembles energy; it has the same dimensions as energy and is therefore measured in joules or ergs. The value of enthalpy is solely dependent on the temperature, pressure, and composition of the system, not on its history.
Enthalpy, denoted by the symbol H, is the sum of the internal energy, denoted by E, and the product of the pressure and volume, denoted by PV.
The change in internal energy is equal to the heat transmitted to, less the work done by, the system, according to the law of energy conservation.
Therefore, Enthalpy is a thermodynamic system's internal energy total as well as the volume times pressure ratio.
To learn more about Enthalpy, refer to the link:
https://brainly.com/question/13996238
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Where are electrons found in an atom?
Answer:
outside the nucleus
Explanation:
Help me I'm desperate :( no links or u will be reported
Answer:
Here is the answer from somewhere in the internet
Lipids include:
A. fats and water
B. Oils and carbohydrates
C. Waxes and sterols
Answer: C
waxes and sterols
Explanation:
edge 2021
How much energy ( in joule ) does the Sun emit in one day (24 hours)? I've previously answered with 3.32, but it was incorrect. Please help thanks.
It is about 3.86 which is 10⁶⁶ watts
Answer:
410 quintillion Joules or 430,000,000,000,000,000,000 Joules
Identify the most and the least basic compound in each of the following sets. Leave the remaining answer in each set blank. a) Sodium acetate: _______ Ammonia: _______ Sodium ethoxide: _______ b) Sodium acetate: _______ Sodium chloroacetate: _______ Sodium fluoroacetate: _______ c) Sodium acetate: _______ Sodium methoxide: _______ Sodium phenoxide:
Answer:
The correct answer is -
a) Sodium acetate: least Ammonia: _______ Sodium ethoxide: most
b) Sodium acetate: most Sodium chloroacetate: _______ Sodium fluoroacetate: least
c) Sodium acetate: least Sodium methoxide: most Sodium phenoxide:
Explanation:
A) In this case the basicity can be found by the stability of the base, Sodium acetate is the most stable base due to resonance stabilization of acetate anion. Sodium acetate is the least basic as the lone pair of electrons involved in the resonance here. An ethoxide ion has more electrons to donate an electron pair easily.
Thus, the correct answer is - Sodium acetate is the least basic while sodium ethoxide is the most basic.
B) Fluroacetate gives a very strong acid and the acetate gives the least strong acid among all three as described in case of a), thus, the most basic is acetate and the least is fluoroacetate.
]C) comparing the acidity of the acids formed by the addition of a proton to the anions is an easy and correct way to find the basicity of compounds.
Acetate ion adds a proton ⇒ acetic acid
methoxide adds a proton ⇒ methanol
phenoxide ion adds proton ⇒ phenol
As it is known that the stronger the acid, the weaker is the conjugate base formed by the loss of the proton.
acetic acid is the strongest acid because it can easily give up its proton to form acetate. Methanol is the weakest among all three and hence methoxide anion is the strongest base.
Thus, the correct answer is - sodium acetate is the least basic while sodium methoxide is the most basic.
What mass of nitrogen (N2) is needed to produce 0.125 mol of ammonia (NH3)? Input a numerical answer only. N2 + 3H2 ---> 2NH:
Please help me
When NH3(g) reacts with O2(g) to form N2O(g) and H2O(l), 342 kJ of energy are evolved for each mole of NH3(g) that reacts. Write a balanced thermochemical equation for the reaction with an energy term in kJ as part of the equation.
Answer: [tex]2NH_3(g)+2O_2(g)\rightarrow N_2O(g)+3H_2O(l)+684kJ[/tex]
Explanation:
The skeletal thermochemical equation for the reaction is:
[tex]NH_3(g)+O_2(g)\rightarrow N_2O(g)+H_2O(l)+342kJ[/tex]
The balanced thermochemical equation for the reaction is:
[tex]2NH_3(g)+2O_2(g)\rightarrow N_2O(g)+3H_2O(l)+684kJ[/tex]
When 1 mole of [tex]NH_3[/tex] reacts with oxygen , heat released = 342 kJ
Thus when 2 moles of [tex]NH_3[/tex] reacts with oxygen , heat released = [tex]\frac{2}{1}\times 342 kJ=684kJ[/tex]
if 23.1g of O2 occupies a volume of 5.0L at a particular temperature and pressure, what volume will 2.50g of Oxygen gas occupy under the same conditions?
Answer:
0.54 L
Explanation:
First we convert the given masses of O₂ into moles, using its molar mass:
23.1 g ÷ 32 g/mol = 0.722 mol2.50 g ÷ 32 g/mol = 0.078 molThen we can solve the problem using Avogadro's law, which states:
V₁n₂=V₂n₁Where:
V₁ = 5.0 Ln₂ = 0.078 molV₂ = ?n₁ = 0.722 molWe input the data:
5.0 L * 0.078 mol = V₂ * 0.722 molAnd solve for V₂:
V₂ = 0.54 LHelp will give brainliest no “click this link”
The longest continuous carbon chain comprises five carbon atoms connected by single bonds, so the root name will be pentane. There is a methyl group (—CH3) attached to carbon 3 (since this molecule is symmetrical, the methyl substituent will always be on carbon 3 regardless of which end you begin counting). Thus, the name of this molecule would be 3-methylpentane.
Suppose you have a 1:1:1 by weight mixture of three solid compounds, salicylic acid 4-nitroaniline naphthalene. You dissolve 1 gram of this mixture in diethyl ether, and place a tiny drop of the ether solution on a TLC plate. After developing the TLC plate, you see three spots. Which compound would would you expect to have the largest Rf value
Answer:
The correct answer is - 4-nitroaniline.
Explanation:
It is given that all three solid compounds salicylic acid + 4-nitroaniline + naphthalene are equal in the ratio in the mixture and then 1 gram of this mixture is dissolved in the diethyl ether and run a drop of the solution on TLC plate. This plate shows three spots.
The salicylic acid and naphthalene would stay dissolved in the diethyl ether solution due to the 4-nitroaniline could be extracted by adding aqueous acid and involve in the aqueous layer and thus spot of 4-nitroaniline would be with largest Rf value.
PLEASE HURRY! What is the name of this alkane?
A skeletal model has a hexagon ring with points at the top and bottom. C H 3 is bonded to the top point, and a carbon and another C H 3 are bonded to the bottom right point.
1-methyl,3-ethylnonane
1-methyl,5-ethylisohexane
1-ethyl,3-methylcyclohexane
1-ethyl,5-methylcyclohexane
Answer:
C. 1-ethyl, 3-methylcyclohexane
(Photo for proof at the bottom.)
Explanation:
The 1-ethyl is because you start numbering from the longest branch, towards the next closest branch. Prefix "eth-" means two, there are 2 carbons in the longest branch. 3-methyl is because the next branch is at number 3, and prefix "meth-" means 1, there is 1 carbon in that chain. "Cyclo" in cyclohexane means the skeletal model is shaped like a ring, and the "hexane" means there are 6 carbons in the ring. Prefix "hex" means 6.
Here's a photo of the unit review on Edge. Refer to the 2nd attachment for a visualization.
Please click the heart if this helped.
Answer:
C. 1-ethyl,3-methylcyclohexane
Explanation:
A student dissolves 15.0 g of ammonium chloride(NH4Cl) in 250. 0 g of water in a well-insulated open cup. She then observes the temperature of the water fall from 20.0 oC to 16.0 oC over the course of minutes. Use this data, and any information you need from the ALEKS Data resource, to answer the questions below about this reaction:
NH4Cl(s) rightarrow NH4+(aq) + Cl-(aq)
You can make any reasonable assumptions about the physical properties of the solution. Note for advanced students: it's possible the student did not do the experiment carefully, and the values you calculate may not be the same as the known and published values for this reaction.
1. Is this reaction exothermic, endothermic, or neither?
2. If you said the reaction was exothermic or endothermic, calculate the amount of heat that was released or absorbed by the reaction in this case.
3. Calculate the reaction enthalpy deltaHrxn per mole of NH4CI.
Answer:
1) Endothermic.
2) [tex]Q_{rxn}=4435.04J[/tex]
3) [tex]\Delta _rH=15.8kJ/mol[/tex]
Explanation:
Hello there!
1) In this case, for these calorimetry problems, we can realize that since the temperature decreases the reaction is endothermic because it is absorbing heat from the solution, that is why the temperature goes from 22.00 °C to 16.0°C.
2) Now, for the total heat released by the reaction, we first need to assume that all of it is released by the solution since it is possible to assume that the calorimeter is perfectly isolated. In such a way, it is also valid to assume that the specific heat of the solution is 4.184 J/(g°C) as it is mostly water, therefore, the heat released by the reaction is:
[tex]Q_{rxn}=-(15.0g+250.0g)*4.184\frac{J}{g\°C}(16.0-20.0)\°C\\\\ Q_{rxn}=4435.04J[/tex]
3) Finally, since the enthalpy of reaction is calculated by dividing the heat released by the reaction over the moles of the solute, in this case NH4Cl, we proceed as follows:
[tex]\Delta _rH=\frac{ Q_{rxn}}{n}\\\\\Delta _rH= \frac{ 4435.04J}{15.0g*\frac{1mol}{53.49g} } *\frac{1kJ}{1000J} \\\\\Delta _rH=15.8kJ/mol[/tex]
Best regards!
Best regards!
I a doing an exam in science pls help.
What type of energy comes from the motion of tiny particles of matter?
Answer:
heat
Explanation:
Answer:
Thermal Energy
Explanation:
NEED HELP FOR THIS ONE
Answer:
C₆H₁₂O₆ + 6 O₂ = 6 CO₂ + 6 H₂O
2 KO₂ + H₂O = 2 KOH + 1.5 O₂
Explanation:
Let's consider the following unbalanced equation.
C₆H₁₂O₆ + O₂ = CO₂ + H₂O
We will start balancing H atoms (higher atomicity) by multiplying H₂O by 6.
C₆H₁₂O₆ + O₂ = CO₂ + 6 H₂O
Then, we will balance C atoms by multiplying CO₂ by 6.
C₆H₁₂O₆ + O₂ = 6 CO₂ + 6 H₂O
Finally, to get the balanced equation, we will multiply O₂ by 6.
C₆H₁₂O₆ + 6 O₂ = 6 CO₂ + 6 H₂O
---
Let's consider the following unbalanced equation.
KO₂ + H₂O = KOH + O₂
We will multiply KO₂ and KOH by 2 to balance K and H atoms.
2 KO₂ + H₂O = 2 KOH + O₂
Finally, to get the balanced equation, we will multiply O₂ by 1.5.
2 KO₂ + H₂O = 2 KOH + 1.5 O₂
5. How many grams of Br is needed to make 1000.g of a 2.0ppm solution?
Answer:
2.0 × 10⁻³ g
Explanation:
Step 1: Given data
Mass of solution: 1000. g (1.000 kg)Concentration of Br₂: 2.0 ppmStep 2: Calculate the mass of Br₂ required to prepare the solution
The concentration of Br₂ is 2.0 ppm, that is, there are 2.0 mg of Br₂ per kilogram of solution. The mass of Br₂ required to prepare 1.000 kg of solution is:
1.000 kg Solution × 2.0 mg Br₂/1 kg Solution = 2.0 mg
Step 3: Convert the mass to grams
We will use the conversion factor 1 g = 1000 mg.
2.0 mg × 1 g/1000 mg = 2.0 × 10⁻³ g
Determine the amount of current going through a 50ohms; resistor with a voltage of 120 v
Answer:
98.356 ohms is the answer
Calculate the percent composition of C in carbon dioxide.
Answer:
27.27%
Explanation:
A student dissolves 10.3 g of potassium chloride (KCI) in 200. g of water in a well-insulated open cup. She then observes the temperature of the water fall from 22.0 °C to 19.0 °C over the course of 6.8 minutes.
KCI(8) → K+ (aq) + Cl- (aq)
You can make any reasonable assumptions about the physical properties of the solution. Be sure answers you calculate using measured data are rounded to the correct number of significant digits.
Required:
Is this reaction exothermic, endothermic, or neither?
Answer:
Endothermic.
Explanation:
Hello there!
In this case, it is possible to answer to the requested question "Is this reaction exothermic, endothermic, or neither?" by looking at the temperature change; thus, since the temperature is diminished from 22.0 °C to 19.0 °C, it is possible to realize that the dissociation reaction:
KCI(8) --> K+ (aq) + Cl- (aq)
Is endothermic as it absorbs heat and therefore the solution gets cooled down. Now for any calculation regarding the heat of reaction, it'd be necessary to assume that the solution has a specific heat equal to the water as the former is mostly composed by the latter and the amount of KCl does not modify the solution significantly.
Best regards!
.35L sample of helium gas is collected at 295 K and 0.98 ATM what volume would this gas occupy at STP
Answer:
0.3857 litres is the answer
True or False?
Weak bases dissociate
completely into (OH)- and
metal cations.
Answer:
False
Explanation:
When weak bases dissociate, an equilibrium is established rather than dissociating 100%. So OH- and metal ions are partially ionized.
wich strong nucleophil h2s or water??and why??
According to my notes, nucleophilicity order is directly proportional to basicity order in an aprotic medium, and is inversely proportional to basicity order in protic medium. And H2O is a stronger base than H2S, so it should be the strong nucleophile, but the answer is given as H2S is the stronger nucleophile.
hope this helped, good luck <3
The compound FeCl3 Is made of.
Answer:
iron and chlorine
Explanation:
1. What volume of a 2.50M Kl(aq) is needed to make 200 ml of a 1.OOM KI)aq)?
Answer:
80 ml
Explanation:
From the question,
Applying Dilution formular
MV = mv................... Equation 1
Where M = Molarity of Kl before dilution, V = Volume of Kl before dilution, m = molarity of Kl after dilution, v = volume of Kl after dilution.
make V the subject of the equation
V = mv/M............. Equation 2
Given: m = 1.00 M, v = 200 ml, M = 2.50 M
Substitute these values into equation 2
V = (1.00×200)/2.50
V = 80 ml
How many moles of NaOH are contained in 56.0 mL of a 2.40 M solution of 1 point
NaOH in water? (**Use only numerical answers with 3 significant figures.
The units are given in the question.)
Your answer
Answer:
1.34 mol
Explanation:
Molarity, which is the molar concentration of a solution, can be calculated by dividing the number of moles (n) by the volume (V).
That is;
Molarity (M) = n/V
According to the information provided in this question;
M = 2.40M
V = 56.0 mL = 56/1000 = 0.056 L
Since molarity = n/V
number of moles = M × V
n = 0.056 × 24
n = 1.34 mol
The formula for chromium (vi)bromate
Answer: The formula of chromium fluoride is CFr2.
Is chemistry required to get into speech language pathology?
Answer:
As of right now (4-7-2021), the physical science requirement for the SLP certificate must be met by completing coursework in the areas of either chemistry or physics.
. Give an example of a salt that is less soluble when the temperature increases
Answer:
cerium (iii) sulfate is less soluble
Answer:
cerium sulphate is less solube when the temperature increase
A 72.0 g sample of an organic solid is dissolved in 180mL of water. The solid is extracted using one 60 mL extraction in the first extraction of an organic solvent which has a partition (distribution) coefficient with water of 10. The first extraction removed 55.4 g of solid from water. What are the numbers that need to go in box A and B to calculate the volume of solvent (y) that would be necessary to remove an additional 7.0g from the remaining sample dissolved in water. You DON'T have to complete the calculation to solve for y.
Answer:
[tex]V_{7.0}\approx 235ml[/tex]
Explanation:
From the question we are told that
mass of sample [tex]M=72.0 grams[/tex]
volume of water [tex]V=180 mL[/tex]
volume for extraction [tex]V'=60mL[/tex]
partition (distribution) coefficient water [tex]d=10[/tex]
initial extraction removal [tex]x=55.4g[/tex]
Generally the equation for the weight of sample [tex]x_n[/tex] is mathematically given by
[tex]x_n=x*(\frac{DV}{DV+V'})^n[/tex]
[tex]x_n=55.4(\frac{10*180}{10*180+60})^1[/tex]
[tex]x_n=53.613g[/tex]
Generally the weight extracted [tex]x_e[/tex] is therefore
[tex]w_e=x-x_n[/tex]
[tex]w_e=55.4-53613[/tex]
[tex]w_e=1.787[/tex]
[tex]w_e=1.787[/tex] is extracted with 60ml solvent .
Therefore volume of solvent (y) that would be necessary to remove an additional 7.0g
[tex]V_{7.0}=\frac{60}{1.767}*7[/tex]
[tex]V_{7.0}=235.030ml[/tex]
[tex]V_{7.0}\approx 235ml[/tex]
