Answer: a for the first one , d for the second one, b for the third one.
Explanation:
Answer:
A: Main sequence star.
B: White Dwarf.
C: Black hole.
Explanation:
Brainliest please.
(HELP) how can you make the metal chair less cold when you sit on it?
Answer:
metal can hold heat keep it near fire
Balance the equation:
Answer:
3SiO2 + 2CaC2 ------> 3Si + 2CaO + 2CO2
Explanation:
Ha hatdog hatdog hatdog because?
Answer:
what's this? s*it fellow
uska dil ker raha tha isleye
write the ground state electronic configuration of an atom having atomic mass number 37 and number of neutrons 20.
Answer: The ground state electronic configuration of an atom having atomic mass number 37 and number of neutrons 20 is [tex]1s^22s^22p^63s^23p^5[/tex]
Explanation:
Atomic number is equal to the number of protons.
Mass number is the sum of number of neutrons and number of protons.
Mass number = number of neutrons + number of protons
37 = 20 + number of protons
number of protons = 17
The atomic number is specific to an element, and the element with atomic number 17 is chlorine.
Electronic configuration represents the total number of electrons that a neutral element contains.
[tex]Cl:17:1s^22s^22p^63s^23p^5[/tex]
Why does the moon's gravitational pull have more effect on Earth's tides than the sun's gravitational pull?
A. The moon is closer to the Earth than the sun.
B.The moon has more mass than the sun.
C. The moon is more dense than the sun.
D. The moon has a greater diameter than the sun.
What is the volume, in liters, of a 0.2 M solution containing 8.5 grams of AgNO3?
Answer:
0.25L or 250Ml
Explanation:
I am not that good but as far as my calculations this must be the answer
37.5g of nitrogen reacts with 15.5 g of hydrogen. What mass of ammonia can be made? What is the limiting reactant?
Answer:
Limiting reactants or limiting reagents decide the amount of product formed and the amount of excess reagent used.
Water's ________ specific heat makes it heat up and cool down slowly; this stability has helped water support life.
A) high
B) low
C) absence of
Answer:
high
Explanation:
Answer:(A)
Explanation:
What are the characteristics of a metallic bond? PLEASE HELP
Answer: Metallic bonding is a type of chemical bonding and is responsible for several characteristic properties of metals such as their shiny lustre, their malleability, and their conductivities for heat and electricity. Both metallic and covalent bonding can be observed in some metal samples
PLEASE MARK ME BRAINLIST
Electrons move freely among positively charged ions. This is the characteristics of a metallic bond. Therefore, the correct option is option B.
Valence electrons in a metallic link are not bound to a specific pair of atoms, but rather travel freely among a "sea" of positively charged metal ions. These electrons are not assigned to any specific atom and are shared by all metal ions in the metallic lattice.
The electron sea model depicts the valence electron arrangement as a "sea" of negatively charged electrons encircling positively charged metal ions. Metals have strong electrical and thermal conductivity due to electron mobility.
Therefore, the correct option is option B.
To know more about metallic bonding, here:
https://brainly.com/question/29766835
#SPJ4
How many pounds of ice are required to absorb 4900 kJ of heat as the ice melts? The heat of fusion of water is 0.334 kJ/g.
Answer:
m = 32.34 pounds of ice.
Explanation:
In this case we need to use the following expression of heat:
q = m * ΔHf (1)
Where:
q: heat absorbed in J or kJ
m: mass of the compound in g
ΔHf: heat of fusion of the water in kJ/g
We are asked to look for the mass of ice in pounds, so after we get the grams, we need to convert the grams to pounds, using the following conversion:
1 pound --------> 453.59 g (2)
So, we have the heat and heat of fusion, from (1) let's solve for the mass, and then, using (2) the conversion to pounds:
q = m * ΔHf
m = q / ΔHf
m = 4900 / 0.334 = 14,670.66 g of ice
Now, the conversion to pounds:
m = 14,670.66 g * 1 pound/453.59 g
m = 32.34 pounds of ice.Hope this helps
PLEASE HELPPP ILL GIVE BRAINLIEST!!!!!!!!!!!!!
Answer:
it travels through the veins
Nitrogen gas is being withdrawn at the rate of 4.5 g/s from a 0.15-m3 cylinder, initially containing the gas at a pressure of 10 bar and 320 K. the cylinder does not conduct heat, nor does its temperature change during the emptying process. What will be the temperature and pressure of the gas in the cylinder after 5 minutes? What will be the rate of change of the gas temperature at this time? Nitrogen can be considered to be an ideal gas with Cp*=30 J/mol.K.
Answer:
Final temperature = 152.57K,
Pressure = 0.6907 bar.
dT/dt = - 1,151 K/s.
Explanation:
The first thing to do here is to write out the equation for mass balance as given below:
dN/dt = N -------------------------------------------------------------------------------------------(1).
N = P/T, then, substitute the values given in the question into:
d[p/T]/ dt = [- 4.5/28 × 8.314]/0.15 = - 8.9 × 10⁻⁵ bar/K.s.
Thus, there is the need to integrate, Integrate [p/T]f = 10/320 - 8.9 × 10⁻⁵ bar/K.s. ------------------------------------(2).
NB; fT = final temperature, fP = final pressure and iT = initial temperature.
Also, [ fT]³⁰/₈.₃₁₄/ [fP] = [iT]³⁰/₈.₃₁₄/ Pi] = [ 320]³⁰/₈.₃₁₄/ 10.
Therefore, [fT]³⁰/₈.₃₁₄ = 109.52 × 10⁶.
Final temperature= [fP]³⁰/₈.₃₁₄ × 169.05.
Note that fP/ [fP]³⁰/₈.₃₁₄ × 169.05 = 10/320 - 8.9 × 10⁻⁵.
Therefore, [fP]¹ ⁻ ³⁰/₈.₃₁₄ = 0.7651.
Hence, Final temperature = 152.57K,
Pressure = 0.6907 bar
dT/ dt = N[RT]² / Cv . PV.
R = 30 - 8.314 = 21.86 J/mol K.
Then, the rate of change of the gas temperature at this time = dT/dt = - 1,151 K/s.
What temperature scale is used in the ideal gas equation?
A. Kelvin
B. Fahrenheit
C. Celcius
D. Doesn't matter
kelvin
hope that helps^^
What is the Ka of a 0.479 M
solution of acetic acid
(CH3COOH) with a pH of 4.76?
r
Answer:
6.31x10^-10
Explanation:
Answer: 6.31 x 10^-10
Explanation:
-
In the reaction: 2X2Y3 + 3Z(QR)4 4X(QR)3 + 3ZY2
What is the charge of the "X" cation needed to form these compounds?
Answer:
That's simple it's the caca of 54 32 x (5) b ÷ 5683jvl done so your answer is 0
[please answer fast!] If the hydroxide ion concentration is 2x10^-3 M, what is the pH of the solution? Show your working.
Answer:
pH = 11.30
Explanation:
pH is defined as -log [H⁺]
To find [H⁺] from [OH⁻] -Concentration of hydroxide ion-, we must use the equilibrium of water:
H₂O(l) ⇄ H⁺(aq) + OH⁻(aq)
Keq = 1x10⁻¹⁴ = [H⁺] [OH⁻]
[H⁺] = 1x10⁻¹⁴ / [OH⁻]
[H⁺] = 1x10⁻¹⁴ / 2x10⁻³M
[H⁺] = 5x10⁻¹²M
pH = -log (5x10⁻¹²M)
pH = 11.30Help me with this please
= 0.2+560.66JK-2eF
use this app : Photomath
It will help you :)
Assume that 41.1g of hydrogen peroxide decompose to produce oxygen gas at STP to the following balanced equation:
2H2O2 (l) ---------> 2H2O(l) + O2 (g)
How many Liters of oxygen gas are produced?
Answer:The hydrogen bond is responsible for many of the anomalous physical and chemical properties of compounds of N, O, and F. In particular, intermolecular hydrogen bonding is responsible for the high boiling point of water (100 °C) compared to the other group 16 hydrides that have much weakerhydrogen bonds
Hydrogen bonding is primarily responsible for the high ______ of water.
why are gases able to spread out and fill whatever container they are in
Answer:
gases are able to spread out and fill whatever container they are in because they do not have. a definite shape their molecules are not tightly packed so they can cover over a vast area like our atmosphere.
Please help!!
You have 5 moles of marbles. How many marbles is this?
Answer:
The answer is 3.011x^24 marbles
Explanation:
6.022 x 10^23 x 5 = 3.011 x 10^24
When calculating the AH of a reaction, why is it important that you include the correct stale symbols in your balanced chemical equation?
Answer: c. so that you use the correct energy states
Explanation:
Enthalpy is the energy release or energy produced when a chemical reaction is carried out.
Enthalpy change is calculated by substracting the energy of reactants from the energy of products.
[tex]\Delta H=H_{products}-H_{reactants}[/tex]
As the energies are different for different states and thus the correct stale symbols in your balanced chemical equation must be given so that we use the correct energy values.
i need help with chemistry asap. the copounds Ch3Oh and Ch3CooH react in the presence of an acid catalyst to form. A. a carboxylic B. an aldehyde C. a ketone and D. an ester.
how does the total mass of each object increases the amount of force that is needed to get them moving at 5 m/s increase by about 200N demonstrate newtons 2nd law
Answer:
The answer is below
Explanation:
Newton's second law of motion states that the force applied to an object is directly proportional to the rate of change of momentum with respect to time, going in the same direction as the force.
Let F = force, m = mass of object, v = velocity of object, mv = momentum.
F = d/dt(mv) = m(dv / dt) = ma; a = acceleration.
Let us assume that the object starts from rest to 5 m/s within 1 seconds, hence:
F = m(dv / dt)
200 N = m[(5 m/s - 0 m/s) / (1 s)]
200 = 5m
m = 40 kg
How many grams are in 21.4 mol Cl2 gas?
Cl2 = 70.9 g/mol
=
[tex]21.4 \: mol \times \frac{70.9 \: g}{1 \: mol} = 1517.26 \: g[/tex]
The
tell
you which element it is.
Atoms of the same element with a different number of NEUTRONS are
Atoms of the same element with a different number of ELECTRONS are
The PROTONS and NEUTRONS Can/Can't leave an atom during a
chemical reaction. The Electrons Can/Can't leave an atom during a
chemical reaction.
In a balanced atom, the
equal the
Answer:
Isotopes
Explanation:
Isotopes are atoms of the same element that contain an identical number of protons, but a different number of neutrons. Despite having different numbers of neutrons, isotopes of the same element have very similar physical properties.
.........m.......................
i need ur help guys
Answer:
Uses of Sodium chloride:
1.it is used as table salt in our diets
2. it is used as a food preservative
3. It is used as an industrial source of sodium and chlorine
Uses of Sodium hydroxide:
1. It is in the laboratory as an alkali in the neutralization of acids
2. It is used in the manufacture of soap
3. It is used in the refining of petroleum
Uses of Sodium carbonate:
1. It is used in the manufacture of detergents and glass
2. It is used to soften hard water
3. it is used to standardize acids in the laboratory
Uses of Sodium sulphate
1. It is used in the manufacture of detergents and glass
2. It is used as a purgative
3. It is used to treat wood-pulp for paper making.
Uses of Potassium nitrate
1. It is used in making gunpowder
2. It is used as rocket propellant
3. It is used in making fertilizer
Uses of Potassium chlorate
1. It is used as an oxidizer
2. It is used in making explosives
3. it is used as a disinfectant
Uses of Potassium permanganate (vii)
1. It is used as an oxidizing agent
2. It is used as a disinfectant
3. It is used as an analytical reagent
Uses of Potassium chloride
1. It is used for the manufacture of fertilizer
2. It is used as an alternative salt to sodium chloride
3. It is used in medicine to treat low blood pressure
2. Potassium nitrate and potassium chloride are used in the manufacture of fertilizers.
Potassium nitrate is used in fertilizers because it provides two important plant nutrients, nitrogen and potassium to plants.
Potassium chloride (potash) is used in fertilizers because it efficiently deliver the important plant nutrient, potassium, to plants.
Explanation:
Uses of Sodium chloride:
1. it is used as table salt in our diets
2. it is used as a food preservative
3. It is used as an industrial source of sodium and chlorine
Uses of Sodium hydroxide:
1. It is in the laboratory as an alkali in the neutralization of acids
2. It is used in the manufacture of soap
3. It is used in the refining of petroleum
Uses of Sodium carbonate:
1. It is used in the manufacture of detergents and glass
2. It is used to soften hard water
3. it is used to standardize acids in the laboratory
Uses of Sodium sulphate
1. It is used in the manufacture of detergents and glass
2. It is used as a purgative
3. It is used to treat wood-pulp for paper making.
Uses of Potassium nitrate
1. It is used in making gunpowder
2. It is used as rocket propellant
3. It is used in making fertilizer
Uses of Potassium chlorate
1. It is used as an oxidizer
2. It is used in making explosives
3. it is used as a disinfectant
Uses of Potassium permanganate (vii)
1. It is used as an oxidizing agent
2. It is used as a disinfectant
3. It is used as an analytical reagent
Uses of Potassium chloride
1. It is used for the manufacture of fertilizer
2. It is used as an alternative salt to sodium chloride
3. It is used in medicine to treat low blood pressure
2. Potassium nitrate and potassium chloride are used in the manufacture of fertilizers.
Potassium nitrate is used in fertilizers because it provides two important plant nutrients, nitrogen and potassium to plants.
Potassium chloride (potash) is used in fertilizers because it efficiently deliver the important plant nutrient, potassium, to plants.
What are mineral acids?
Answer:
mineral acids are obtained from one or more inorganic compounds which is a compound that lacks carbon and hydrogen bonds. Inorganic compound examples include water and carbon dioxide. Something all mineral acids do is form hydrogen ions and the joined together bases when it is dissolved in water.
Explanation:
HELP ASAP!!!!!! 30 PTS
Mouth, throat, kidney, and stomach cancers can each be linked to a common cause.
Which can be a cause of any of these cancers?
UV radiation
tobacco use
diabetes
sickle cell anemia
Answer:
Tobacco use
Explanation:
Smoking causes cancer, heart disease, stroke, lung diseases, diabetes, and chronic obstructive pulmonary disease (COPD), which includes emphysema and chronic bronchitis. Smoking also increases risk for tuberculosis, certain eye diseases, and problems of the immune system, including rheumatoid arthritis
Answer:
c. Tabaco use
Explanation:
A sample of an oxide of nitrogen is found to contain 30.4% nitrogen. What is its empirical formula?
Answer:
If nitrogen = 30.4% then oxygen = 100-30.4 = 69.6%
divide each % value by atomic mass
N = 30.4/14 = 2.17
O = 69.6/16 = 4.35
Divide each y smaller:
N = 2.17/2.17 = 1
O = 4.35/2.17 = 2
Explanation:
"The empirical Formula will be [tex]NO_{2}[/tex]."
What is empirical formula?
In chemistry, an empirical formula is the simplest thought of the entire number quantity of atoms in a molecule.
It is given that N = 30.4%.
The % of O can be determined as: 100-30.4%= 69.65.
Now, after dividing % value with atomic mass, we get.
Mass of N= 14 and Mass of O = 16.
N= 30.4/14= 2.17
O = 69.6/ 16= 4.35
It can be seen that N has less number as compared to O . So, divide each with 2.17.
N= 2.17/2.17 = 1
O = 4.35/2.17=2
So the empirical formula will be [tex]NO_{2}[/tex].
To know more about empirical formula click here.
https://brainly.com/question/21280037.
#SPJ2
consider a sample of compound contain 1.719c 0.284gh so find emprisical formula