Answer:
A I did the exam and I saw A sorry if it is wrong dont have the best of memory
what form of energy causes an ice cube to melt
A.mechanial
B.magnetic
C.sound
B.thermal
Answer:
Thermal
Explanation:
When something heats up its atoms become further apart making it melt when something heats up or gets heat or loses heat that's thermal energy
What makes an object cool down?
A) adding cold molecules
B) subtracting heat molecules
C) increasing the kinetic energy of the molecules
D) Decreasing the kinetic energy of the molecules
Answer:
D) decreasing the kinetic energy of the molecules
Explanation:
A compound with a formula mass of 45.08 g/mol is found to be 85.64% Carbon and the remainder Hydrogen. Find the molecular formula:
Someone took the last cookie from the cookie jar last night. The last person to leave the scene is the culprit. Who was it? Highlight the guilty culprit based on the clues provided.
Balanced or Unbalanced
K+2MgBr=KBr+Mg
Please help with the chart
Answer:
no
Explanation:
8. Which is correct about kinetic energy?
As the kinetic energy increases gas molecules move slower
B. As the kinetic energy increases, the temperature of the gas increases
C. As the kinetic energy decreases, gas molecules move faster
D. As the kinetic energy decreases, the temperature of the gas increases
Answer:
is B
Explanation:
Please answer. Thank you
Answer:
Explanation:
what are tho anwser choices
The systematic pattern for filling up the electron configuration, from low energy to high energy for an element is called the:_________
a) the Pauli exclusion principle.
b) Hund's rule.
c) Coulomb's law the Aufbau principle.
d) the Heisenberg uncertainty principle.
Answer: The Aufbau principle.
Explanation:
According to aufbau's principle of filling electronic orbitals, the sublevels with lower energies are filled up before those with higher energies. The orbitals with lower (n+l) value will be filled prior to higher (n+l) value.
Hunds rule states that an orbital can contain two electrons only if all other orbitals in that sublevel contain at least one electron.
Paulis exclusion principle states that two electrons must have opposite spin , which means that no two electrons can have same set of quantum numbers.
Heisenberg principle states that it is impossible to measure simultaneously the exact position and momentum of subatomic particle.
Answer:
option c
hope helps you have a great day
Helpppp I’m being timed !!
Answer:
pp
Explanation:
Explanation:
goodluck to your test!
As the number of bonds increases, the strength of the bond ________.
Answer:
increases
Explanation:
true or false the human body system works together to maintain
Answer:
Im pretty sure it would be true
Explanation:
The concentration of KBr in a solution prepared by dissolving 2.21g of KBr in 897 g of water is __________ m.
A) 2.46.
B) 0.0167.
C) 2.07 x 10-5.
D) 0.0186.
E) 0.0207.
Answer:
E) 0.0207
Explanation:
The molal concentration, m, is defined as the ratio between moles of solute (In this case, KBr) per kg of solvent (water):
Moles KBr -Molar mass: 119g/mol-
2.21g KBr * (1mol / 119g) = 0.01857moles
Mass solvent:
897g * (1kg / 1000g) = 0.897kg
Molal concentration:
0.01857 moles / 0.897kg =
0.0207m
Right solution is:
E) 0.0207.A metal ion uses d2sp3 orbitals when forming a complex. What is its coordination number and the shape of the complex?
Answer:
Octahedral
Explanation:
The idea of hybridization is a valence bond concept introduced by Linus Pauling and soon became an important explanation for the structure of molecules even in coordination chemistry.
Hybridization involves the mixing of orbitals of appropriate energy to form a new set of orbitals that are more suitable for bonding with ligands.
When one s, two d and three p orbitals are hybridized in complex formation, octahedral complexes are formed.
Can someone help me and explain why they got what they got?
Answer:
24.32 amu
Explanation:
From the question given above, the following data were obtained:
Isotope A (Mg–24):
Mass of A = 24 amu
Abundance (A%) = 79%
Isotope B (Mg–25):
Mass of B = 25 amu
Abundance (B%) = 10%
Isotope C (Mg–26):
Mass of C = 26 amu
Abundance (C%) = 11%
Average atomic mass of Mg =?
Average atomic mass = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
= [(24 × 79)/100] + [(25 × 10)/100] + [(26 × 11)/100]
= 18.96 + 2.5 + 2.86
= 24.32 amu
Thus, the average atomic mass of Mg is 24.32 amu
If the resistance of a circuit is 3 ohms, and the voltage produced by the cell in the circuit is 12 volts, what's the magnitude of the current?
Answer:
4 AExplanation:
The magnitude of the current can be found by using the formula
[tex]i = \frac{v}{r} \\ [/tex]
v is the voltage
r is the resistance
From the question we have
[tex]i = \frac{12}{3} = 4 \\ [/tex]
We have the final answer as
4 AHope this helps you
Answer:
4A
Explanation:
Rocks melt at what temperature range? a. 50 to 100 degrees Celsius b. 130 to 200 degrees Celsius c. 220 to 500 degrees Celsius d. 600 to 1,300 degrees Celsius
600 and 1,300 degrees Celsius
In pretty sure
What is the electron configuration for N (nitrogen)?
A. 1s22s23s23p1
B. 1s21p5
C. 1s22s22p3
D. 1s22s22p23s1
Explanation:
₇N = 1s² 2s² 2p³
Group = 15period = 2atomic mass = 14Hydride of Nitrogen = Ammoniavalency = 3Therefore,
Option C is correct ✔
When forming an ion, nitrogen will have what charge?
Answer:
The valence electrons of nitrogen in its compounds are all sp³ hybridized orbitals. The formal charge on N is usually -1 for an anion, 0 for a neutral compound, and +1 in cations. A nitrogen atom with a formal charge of -3 would correspond to a nitride ion, N³⁻, which is strongly basic in aqueous solution. Hope this helps...
Explanation:
Brainliest please?
Percent yield is very important in terms of money. The higher the percent yield, the more of a product you can make. If you are working for a drug company and your theoretical yield is 120 kg, but you actually made 105 kg, what is your percent yield?
A. 8.75%
B. 114%
C. 87.50%
D. 15.00%
Answer:
87.5 %
Explanation:
Step 1: Given data
Theoretical yield: 120 kgReal yield: 105 kgStep 2: Calculate the percent yield
When working with chemical reactions, we can determine the efficience in obtaining a product measuring the percent yield. The theoretical yield is the maximum amount of product that we could obtain according to the stoichiometry, whereas the real yield is the amount of product that we actually obtain when we carry out the process. We can calculate the percent yield usign the following expression.
%yield = real yield / theoretical yield × 100%
%yield = 105 kg / 120 kg × 100%
%yield = 87.5 %
How much excess reactant remains from the reaction of 8.3g of sodium and 4.5g of chlorine?
a. 8.2g Na
b. 5.4g Na
c. 5.4g Cl2
d. 8.2g Cl2
Answer:
5.4 g Na
Explanation:
Calculate the mass of sodium chloride from both reactants. The lesser value is the amount is the theoretical yield. Subtract the mass of the calculated mass of sodium chloride from the mass of the reactants.
An ice cube melts on the warm sidewalk on a hot summer day. Let the entropies of the ice cube, of the pavement and of the ice cubesidewalk system be Sice, Ssw and Ssys. What happens to these entropies?
1. Sice increases, Ssw decreases, Ssys does not change.
2. Sice decreases, Ssw increases, Ssys decreases
3. Sice increases, Ssw decreases, Ssys increases
4. Sice increases, Ssw increases, Ssys increases
Answer:
3. Sice increases, Ssw decreases, Ssys increases
Explanation:
Entropy basically refers to the degree of disorderliness of a system.
Ice Cube --> As the ice cube melts, it undergoes a change in state of matter from solid to liquid hence it's entropy increases as the degree of movement of its molecules is more disordered in the liquid state.
This means the likely options are; 1, 3 and 4.
Sidewalk --> The entropy here decreases as the ice melts on the side walk. This is because there is a reduction in temperature. Entropy is directly proportional to temperature. Decrease in temperature leads to decrease in entropy.
This means the likely option is 1 and 3
The net entropy change of the system is however positive.
The density of aluminum is 2.7 g/cm3 and that of Al2O3 is about 4 g/cm3. Calculate the PB ratio for Aluminum. (Hint: The Pilling-Bedworth Ratio (PBR) gives the volume of oxide formed to the volume of metal atoms.)
a) 1.28
b) 0.28
c) 0.75
Answer:
1.28
Explanation:
Al = aluminium
Density of Al = 2.7g/cm³
Density of Al2O3 = 4g/cm³
Molecular weight of Aluminum = 27g/mol
Molecular weight of Al2O3= 101.96 g/mol
Pilling bedworth ratio = Rob
= M(Al2O3) * density of Al / n* molecular weight of Al * density of Al2O3
= 101.96g/mol x 2.7g/cm³/2x 27g/mol x 4g/cm³
= 275.292/216
= 1.28
From the calculation above 1.38nis the PB ratio for aluminum
What can you say about the pH before and after the last drop of HNO3 was added?
Answer:
the water symbol i forgot tho
Explanation:
hi
NaOH is a base. Therefore, the pH is initially very high and above 7. If you add HNO3, which is a strong acid and has a pH less than 7, you will lower the pH of the solution. In fact, at the equivalent curve, you will have a pH of 7 because you are mixing a strong acid and strong base. Depending on how much HNO3 is added, the pH will continue to go down.
Chemistry problem. please help
Answer:
solid X contains only ionic bond, and solid Y contains only covalent bonds.
Explanation:
solid X contains only ionic bond, and solid Y contains only covalent bonds. Because ionic compounds they have high melting point compared to covalent compounds, ionic compound they are generally insoluble in non polar solvent such as toluene but soluble in polar solvent such as water, ionic compound they conduct electricity.
What is the net ionic equation for the acid-base reaction between chlorous acid and sodium hydroxide?
Answer: [tex]HCO_2(aq)+OH^-(aq)\rightarrow ClO_2^-(aq)+H_2O(l)[/tex]
Explanation:
Neutralization is a chemical reaction in which an acid and a base reacts to form salt and water.
Spectator ions are defined as the ions which does not get involved in a chemical equation or they are ions which are found on both the sides of the chemical reaction present in ionic form.
The reaction of chlorous acid (weak acid) and sodium hydroxide (strong base) is written as:
[tex]HClO_2(aq)+NaOH(aq)\rightarrow NaClO_2(aq)+H_2O(l)[/tex]
The equation can be written in terms of ions as:
[tex]HClO_2(aq)+Na^+(aq)+OH^-(aq)\rightarrow Na^+(aq)+ClO_2^-(aq)+H_2O(l)[/tex]
The ions which are present on both the sides of the equation are sodium ions and hence are not involved in net ionic equation.
Hence, the net ionic equation is :
[tex]HCO_2(aq)+OH^-(aq)\rightarrow ClO_2^-(aq)+H_2O(l)[/tex]
Please help me please!!
(Picture above)
Answer:
I'll tell you how to find it, but no answers
Explanation:
It's pretty simple. Your north and south points go first, then your east and west. You look at the dot, and trace your finger down the two lines to get your lattitude and longitude. From there, you just write it out. For example, G would be at (0,0) because the lines match up at 0,0 where the point is.
which orbital has the highest energy level
Answer:
p orbitals
Explanation:
The half-life of the radioisotope 158Eu is 0.77 h. How much time is required for a 160.0-g sample of 158Eu to decay to 2.07 g?
a. 3.0 h
b. 4.0 h
c. 6.0 h
d. 2.1 h
e. 4.8 h
Answer: e. 4.8 h
Explanation:
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant
a - x = amount left after decay process
a) for rate constant
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
[tex]t_{\frac{1}{2}}=\frac{0.693}{k}[/tex]
[tex]k=\frac{0.693}{0.77hr}=0.9hr^{-1}[/tex]
b) for 160.0 g to decay to 2.07 g
[tex]t=\frac{2.303}{0.9}\log\frac{160.0}{2.07}[/tex]
[tex]t=4.8hr[/tex]
The time required for a 160.0-g sample of 158Eu to decay to 2.07 g is 4.8 hours
Explain how atoms organize to create larger structures?
Answer:
First of all they are super tiny particles of neutrons, electrons and protons. Then they come together to organize a structure of atom. Atoms come together to form a molecule and smaller molecules work together to form macromolecules. Thus, how they organize and form building blocks of a substance.
Hope it helps!<3
