Answer: If the gold in the crown was mixed with a less-valuable metal such as bronze of copper then this affects its density by making it to weigh even more and if it weighs more then it has less of chance to float. Observe: Drag each of the crowns into the liquid.
Explanation:
Density can be defined as the compactness of any substance. It is the mass/volume of a substance.
The density of gold is 19.3 g/ccThe density of copper is 9 g/ccThe density for bronze is 8.73 g/cc.Thus, if the gold crown is mixed with cheaper substances, such as bronze and copper, the density of the crown will decrease and it will become lighter.
https://brainly.com/question/24386693
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]
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
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.Need help please? Thanks youu
Answer:
A
B
E
Explanation:
"Fission is the splitting of a heavy, unstable nucleus into two lighter nuclei
and fusion is the process where two light nuclei combine together releasing vast amounts of energy"
a process that releases energy is respiration
True or False: Cohesion is the attraction between particles of the same
substance
Answer: True
Explanation:
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.
Please help!! On a timer!! If you can help me with any of the following questions please, I'm lost.
1. What is the density of a block of marble that occupies 251 cm^3 and has a mass of 933 g? Answer in units of g/cm^3
2. Lee pushes horizontally with a force of 45 N on an 18 kg mass for 12 across the floor. Calculate the amount of Lee did. Answer in units of J.
3. What is the mass number of an element with atomic number 10 and 10 neutrons.
Answer:
3. Answer= Neon (Ne) is the Group 8A chemical element that has atomic number 10 and mass 20.1797.
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.
Balanced or Unbalanced
K+2MgBr=KBr+Mg
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:
how many molecules of nitrogen are in 1.25 mol N2?
Answer:
7.52 x 10²³ molecules N
Explanation:
multiply 1.25 mol of N2 by Avogadro's Number
true or false the human body system works together to maintain
Answer:
Im pretty sure it would be true
Explanation:
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:
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?
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:
Please answer. Thank you
Answer:
Explanation:
what are tho anwser choices
A sample of gas occupies a volume of 350.0 mL at 840mm Hg and 33°C. Determine the volume of this sample at 600 mm By and 52°C
Answer:
V₂ = 520.42 mL
Explanation:
Given data:
Initial volume = 350.0 mL
Initial pressure = 840 mmHg
Initial temperature = 33°C (33 +273 = 306 K)
Final temperature = 52°C (52+273 = 325 K)
Final volume = ?
Final pressure = 600 mmHg
Formula:
P₁V₁/T₁ = P₂V₂/T₂
P₁ = Initial pressure
V₁ = Initial volume
T₁ = Initial temperature
P₂ = Final pressure
V₂ = Final volume
T₂ = Final temperature
Solution:
V₂ = P₁V₁ T₂/ T₁ P₂
V₂ = 840 mmHg × 350.0 mL × 325 K / 306 K × 600 mmHg
V₂ = 95550000 mmHg.mL.K /183600 K.mmHg
V₂ = 520.42 mL
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 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
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
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
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.
What is a solute?
A material that is dissolved in another material.
O A material in which another material is dissolved.
An area of space surrounding the nucleus.
O Chemical formulas on the left side of an equation.
Most elements are __ at room temperature
Answer:
Most elements are Solids at room temperature
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.
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.
Which of the choices below is matter? *
electricity
wood
sound
O
fire
Answer:
Wood
Explanation:
Matter is anything that has mass. Nor sound, fire or electricity have mass which leaves wood as the final answer.
As the number of bonds increases, the strength of the bond ________.
Answer:
increases
Explanation:
Please help with the chart
Answer:
no
Explanation:
PLEASE HURRY!!! I WILL GIVE BRAINLEIST!!!!
Study the diagram of a cell. Which structures are found in both plant and animal cells? W and X W and Z X and Y O Y and Z XN Y -W
Answer:
A I did the exam and I saw A sorry if it is wrong dont have the best of memory
