1. Consider the following: HCl (aq) + NaOH (aq) → NaCl (aq) + H2O (liq) ∆H = -57.62 kJ/mol
If a 25.0 mL of 0.144 M HCl (aq) at 25oC is added to 20.0 mL of 0.132 M NaOH (aq) at 25oC, calculate the final temperature of the contents. Assume the volumes are additive and that the resulting salt water solution has a density of 1.04 g/mL with a specific heat capacity of 3.93 J/goC. Note that you will also need to determine the limiting reactant.
Answer:
25.82°C
Explanation:
Based on the reaction, 1 mole of HCl and 1 mole of NaOH reacts, that means the reaction is 1:1. The moles of each compound are:
Moles HCl:
0.025L * (0.144mol/L) = 0.0036 moles HCl
Moles NaOH:
0.020L * (0.132mol/L) = 0.00264 moles NaOH
Thus, moles of reaction are 0.00264 moles
The heat released in a calorimeter is obtained using the equation:
Q = m*c*ΔT
Where Q is heat released in the reaction:
0.00264 moles * (-57.62kJ/mol) = 0.1521kJ = 152.1J of reaction
m is mass of the solution:
25.0mL + 20.0mL = 45mL * (1.04g/mL) = 46.8g
c is specific heat of the solution:
3.93J/gºC
And ΔT is change in temperature.
Solving for ΔT:
Q /mc = ΔT
151.2J / 46.8g*3.93J°C = 0.82°C = ΔT = Final temperature - Initial temperature.
Final temperature = 0.82°C + 25°C =
25.82°C
How are salinity, temperature and circulation related?
Answer:
Salinity, along with temperature, determines the density of seawater, and hence its vertical flow patterns in thermohaline circulation. 2. Salinity records the physical processes affecting a water mass when it was last at the surface. Hope this helps!
Explanation:
If 25.6 mL isopropyl alcohol fully decomposes, what mass of H2 is formed? The density of isopropyl alcohol is 0.785 g/mL. g
Answer:
The correct answer is 0.67 g H₂
Explanation:
Isopropyl alcohol (C₃H₇OH) can decompose to give acetone (C₂H₆OH) and hydrogen gas (H₂) according to the following chemical equation:
C₃H₇OH (g) ⇒ C₂H₆CO(g) + H₂(g)
We can calculate the initial mass of isopropyl alcohol from the density and volume data:
density = m/V = 0.785 g/mL
⇒ m = density x V = 0.785 g/mL x 25.6 mL = 20.096 g C₃H₇OH
According to the chemical equation 1 mol of C₃H₇OH gives 1 mol H₂. The molar mass of C₃H₇OH is:
molar mass C₃H₇OH = (12 g/mol x 3) + (1 g/mol x 7) + 16 g/mol + 1 g/mol = 60 g/mol
molar mass H₂ = 1 g/mol x 2 = 2 g/mol
So, we obtain: 2 g H₂ from 60 g C₃H₇OH. We multiply this stoichiometric ratio (2 g H₂/60 g C₃H₇OH) by the initial mass of C₃H₇OH to obtain the mass of H₂ is formed:
20.096 g C₃H₇OH x (2 g H₂/60 g C₃H₇OH) = 0.6698 g ≅ 0.67 g H₂
Atomic radius is....
O The tendency for an atom to attract electrons
The energy required to remove an electron
O The energy required to add an electron
O The distance from the nucleus to the last orbital
In a fluorine atom, on which energy level are the valence electrons found?
Answer:
second energy level
Explanation:
Valence electrons are those electrons which are present in outer most orbital of the atom.
This can be easily found through the electronic configuration of atom.
Electronic configuration of F:
F₉ = 1s² 2s² 2p⁵
We can see that the valence electrons are present in second energy level of F atom.
There are seven valence electrons of fluorine.
It is called halogens.
Halogens are very reactive these elements can not be found free in nature. Their boiling points also increases down the group which changes their physical states. i.e fluorine is gas while iodine is solid.
Fluorine:
1. it is yellow in color.
2. it is flammable gas.
3. it is highly corrosive.
4. fluorine has pungent smell.
5. its reactions with all other elements are very vigorous except neon, oxygen, krypton and helium.
Can someone help me with this chemistry I have attached?, just helping me understand these problems. Its moles and questions
I need help with this please
Thank you
Answer:
From fastest to slowest its: (4)A to B, (1)E to F, (3)C to D, (2)D to E
Explanation:
The steeper the line is the faster she went. D to E she didn't make any progress because the line is straight. Sry I'm terrible at explaining things.
How many grams of H2SO4 are needed to prepare 5.0 L of a 2 M H2SO4 solution? You must show your work in order to receive credit.
What happens when the elements in group 2 react with water?
Answer:
The Group 2 metals become more reactive towards the water as you go down the Group.
Explanation:
These all react with cold water with increasing vigour to give the metal hydroxide and hydrogen. ... You get less precipitate as you go down the Group because more of the hydroxide dissolves in the water. Summary of the trend in reactivity.
Please mark me brainliest! hope this helped!
God bless!
Which element is classified as a noble gas?
Answer:
any of the seven chemical elements that make up Group 18 (VIIIa) of the periodic table. The elements are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn), and oganesson (Og). :)
Explanation:
Answer:
For edge, the answer is;
D. Xe
(Xenon)
Explanation:
edg- answers ;p
The data table shows the number of pumpkin seeds that germinate at different temperatures. What is the median number of seeds that germinate at 24C?
A. 80.5 B. 82 C. 78.5 D. 80
Answer:
Explanation:
80
3.54 millilelvin = ? kelvin
The process of reviewing information using an investigator is knowledge, training, experience, and expertise is what type of reasoning?
Answer:
Inductive reasoning
Explanation:
Inductive reasoning is based on making broad generalizations from specific observations. We draw conclusions from the data we have. This is the opposite of deductive reasoning, which starts with a general statement and aims to reach a specific conclusion.
Based on this, we can conclude that, if an investigator uses their knowledge, training, experience, and expertise to reach a conclusion, they are using inductive reasoning.
experiment to determine the
ity of a free-falling object. Data
are presented in the table.
If the accepted value of acceleration due to gravity is
9.8 m/s2, how would you describe Clara's data?
Measurement
O precise but not accurate
accurate but not precise
both accurate and precise
neither accurate nor precise
9.3 m/s2
7.3 m/s2
7.5 m/s2
8.9 m/s2
Ok
help me please loves
Answer:
K and ba
Explanation:
Answer: K and Ba
Explanation:
Please help with number 7 thank you! 30 points
Answer:
X indicates proteins Y indicates lipids
Explanation:
X shows membrane bound proteins. Y shows lipids in the plasma membrane.
Answer:
I think that x indicates proteins and y indicates lipids
Explanation:
Proteins often are channels that help things get in and out of the cell, and x looks like one.
Membranes are made of phospholipids, which are types of lipids. Y is a lipid.
Write both the complete electron-configuration notation and the noble-gas notation for a barium atom.
Answer:
Explanation:
Noble gas notation: [Xe] 6s2
Complete Electron Configuration: 1s22s22p63s23p63d104s24p64d105s25p66s2.
(ik kinda hard to understand but i looked it up ant it works)
Answer:
Complete Electronic Configuration:
1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²
Electronic Configuration in Noble Gas Notation:
[Xe] 6s²
A species that has 13 protons and 10 electrons will be_____
Answer: Aluminum
Explanation:
Al3+ indicates an ion of aluminum having a charge of + 3. I.e., since an aluminum atom normally has 13 protons and 13 electrons, this ion has 10 electrons (-10 charge) and 13 protons (+ 13 charge) giving it a charge of + 3 (-10 + 13 = +3).
Answer:
Explanation:
Al3+ indicates an ion of aluminum having a charge of + 3. I.e., since an aluminum atom normally has 13 protons and 13 electrons, this ion has 10 electrons (-10 charge) and 13 protons (+ 13 charge) giving it a charge of + 3 (-10 + 13 = +3).
ccto.
Rank these systems in order of decreasing entropy. Rank from highest to lowest entropy.
a. 1 mol carbon tetrafluoride gas at 273k 40L
b. 1 mol krypton gas at 273K 40L
c. 1/2 mol krypton gas at 100k 20L
d. 1 mol krypton gas at 273K 20L
e. 1/2 mol krypton liquid at 100K
f. 1 mol fluorine gas 273 K 40L
g. 1/2 mol krypton gas at 273K 20L
Answer:
The answer is "order will be A > F > B> D > G > C > E".
Explanation:
Entropy is disunity, the greater the lack of organization the entropy. When two gases use the same moles, then more entropy is achieved for a larger number of atoms in the molecule (even with more macrostates). Its smaller your volume the less the molecules may circulate, reducing as well as the amount of potential different countries and thus the entropy. Molecules or atoms in colder gas are much less active so they do not actually take so many various energy states and therefore less entropy. In colder gas. A liquid is requested more so than gas and its randomness decreases.Which is not the name of a family on the periodic table
a) Halogens
b) Noble Gases
c) Alkali Earth Metals
d) Actinides
;
Explanation: Look at the scrrn shot and you can see what is on there or not. :)))))
Actinides are not the name of the family of the periodic table.
Explanation:
In the modern periodic table :
Elements are arranged on the basis of their atomic numbersThere are 18 groups(vertical groups) and 7 periods (horizontal rows)Groups are also called families of the periodic table.Metals are present from the middle to the left-hand side of the periodic tableNonmetals are present on the upper right-hand side of the periodic tableMetalloids divide the periodic table in a zig-zag line with nonmetals on the right and metals on the left.The alkali metals are present under group 1The alkaline earth metals are present under group 2The noble gases are present under group 18The halogens are present under group 17The elements in separate two horizontal rows in the bottom are lanthanides and actinides.So, from this, we can conclude that actinides are not the name of the family of the periodic table.
Learn more about the periodic table:
brainly.com/question/226164?referrer=searchResults
brainly.com/question/1447213?referrer=searchResults
Li atoms in 3.7 moles
Answer:
We know that there are 6.022 * 10²³ atoms in 1 mole of any element
So, that means that there are 6.022 * 10²³ atoms in 1 mole of Li (Lithium)
Atoms in 3.7 Moles:
atoms in one mole = 6.022 * 10²³
atoms in 3.7 moles = 6.022 * 10²³ * 3.7
atoms in 3.7 moles = 22.28 * 10²³
atoms in 3.7 moles = 2.228 * 10²⁴
Reactions are classified as either exothermic or endothermic. . ____________ reactions feel hot (e.g., a burning campfire), whereas _________reactions feel cool.
Answer:
Exothermic reactions feel hot
Endothermic reactions feel cool
Explanation:
In an exothermic reaction, heat is given out by the system. The energy of the reactants is greater than that of the products hence the excess energy is given off as heat. The reaction vessel feels hot.
In an endothermic reaction, the energy of products is greater than that of the reactants hence energy is taken into the system and the reaction vessel feels cool.
SOMEONE PLEASE HELPPP
Antoine Lavoisier correctly characterize as an element?
Which of the following are mole ratios from the balanced chemical equation below? Select all that
apply.
FeCl3 + 3HF - FeF3 + 3HCI
1 mole HF/1 mole HCI
3 mole HF/1 mole FeF3
1 mole FeCl3/3 mnole HF
3 mnole HF/1 mole FeCl3
The mole ratio of the given reaction is 1 mole HF/1 mole HCI; option A.
What are mole ratios?Mole ratios are ratios of the moles of reactants and products in a balanced chemical equation of a reaction.
Mole ratios are obtained from balanced chemical equations.
The balanced equation of the reaction is given below:
FeCl3 + 3HF ----> FeF3 + 3HCIThe mole ratio of the given reaction is 1 mole HF/1 mole HCI.
Learn more about mole ratio at: https://brainly.com/question/19099163
#SPJ1
A gas mixture contains HBr, NO2, and C2H6 at STP. If a tiny hole is made in the container, which gas will effuse fastest? NO2 C2H6 HBr They all effuse at the same rate. Which gas molecules have the highest average kinetic energy at this temperature? HBr NO2 C2H6 They all have the same average kinetic energy.
Answer:
C2H6
Explanation:
Let us first consider the molar Masses of each gas
HBr - 80.91 g/mol
NO2 - 46.0055 g/mol
C2H6 - 30.07 g/mol
We must remember that the greater the molar mass of a gas the lesser its velocity and average kinetic energy.
Looking at the gases listed, C2H6 have the highest average kinetic energy at this temperature since it has the lowest molecular mass. This reasoning is directly derived from Graham's law of diffusion in gases.
Hence C2H6 will effuse fastest when a hole is made in the container. It also possess the greatest average kinetic energy because it has the lowest molecular mass.
Ok
A plant part that contains a tiny new plant, or embryo
seed
spore
root
flower
How can a shoreline be destroyed by a Hurricane?
Answer:
costal erosion
Explanation:
can cause erosion
Answer:
The water piles up with nowhere to go but onto land when it gets to the coast. The rising water, called storm surge, can submerge low-lying areas and towns along the coast. Combined with the crashing waves of the storm, the storm surge can cause demolishing docks, houses, roads, and erode beaches.
Explanation:
Which of these properties is physical property of aluminum
A. Aluminum rusts when it is exposed to moisture and air
B. Aluminum is a good conductor of heat
C. Aluminum reacts with oxygen to form aluminum oxide
D. Aluminum reacts with hydrochloric acid to give up aluminum chloride and hydrogen gas
Answer:
B. Aluminum is a good conductor of heat
Explanation:
Physical properties are usually those that can be observed using our senses such as color, luster, freezing point, boiling point, melting point, density, hardness and odor. The Physical Properties of Aluminum are as follows: Color : Silvery-white with a bluish tint.
Answer:
I know that it is D for sure
Examples 36
A cylinder is 350cm³ long and two gases A and B have relative molecular weights of 64 and 16 respectively. If the two gases, at the same temperature and pressure, are released simultaneously at both ends determine the distance from one end at which the gases meet.
2x = 350- x
3x = 350
x = 350/x
therefore,
x = 116.67cm.
so, (350 - x)cm³ = (350- 166.67)cm³ = 233.33cm³
Hence distance covered by gas A is 116.67cm that by B is 233.33cm