Answer:
A
Explanation:
the nervous system helps parts of the body communicate.through nerves.
I hope this helps
PLZ HELP ME Which of the following is the process by which chloroplasts use carbon dioxide, water, and sunlight to produce sugars and oxygen?
A. Photosynthesis
B. Cellular respiration
c. Reproduction
D. Homeostasis
Answer:
a
Explanation:
Determinar el volumen de 20 kg de benceno si su densidad es de 0,88g/cm3
Answer:
volume = mass/ densidad
0.88g/cm3 = 880kg/m3
v=20kg/880kg/m3
v=0.02272727272
o puede ser 0.0227
o tambien puede ser 0.023
Compare and contrast qualitative and quantitative data.
Answer: Qualitative data typically consists of words while quantitative data consists of numbers.
Explanation:
how can you identify if a physical or chemical change has occurred
Answer:
The difference between a physical reaction and a chemical reaction is what its made of. In a chemical reaction, there is a change in the materials of the substances in question; in a physical change there is a difference in the appearance, smell, or simple display of a sample of matter without a change in composition. Whereas will a chemical change there is not.
Answer:
Answer:
Physical changes are changes affecting the form of a chemical substance, but not its chemical composition. Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds. Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. Some signs of a chemical change are a change in color and the formation of bubbles. The five conditions of chemical change: color chage, formation of a precipitate, formation of a gas, odor change, temperature change. Change in Color. Noticeable Odor (after reaction has begun) Formation of a Precipitate. Formation of Bubbles. Physical changes are changes that do not alter the identity of a substance. Chemical changes are changes that occur when one substance is turned into another substance. Chemical changes are frequently harder to reverse than physical changes
Explanation:
Which of the following pairs of compounds have the same empirical formula?
a. acetylene, C2H2, and benzene, C6H6
b. ethane, C2H6, and butane, C4H10
c. nitrogen dioxide, NO2, and dinitrogen tetroxide, N2O4
d. diphenyl ether, C12H10O, and phenol, C6H5OH
Answer:
option a and c both are correct
Explanation:
please mark me as brainliest
The pairs of compounds have the same empirical formula are:
a. acetylene, C₂H₂, and benzene, C₆H₆ and
c .nitrogen dioxide, NO₂, and di nitrogen tetroxide, N₂O₄
What is empirical formula?The empirical formula of a compound is defined as the formula that shows the ratio of elements present in the compound, but not the actual numbers of atoms found in the molecule.
In some cases, the empirical formula is the same as the molecular formula, which gives the actual number of atoms in a compound (e.g., H₂O).Otherwise, the molecular formula is a multiple of the empirical formula (e.g., CH₂O is the empirical formula for glucose, C₆H₁₂O₆).
Examples of empirical formulas:
Glucose has a molecular formula of C₆H₁₂O₆. It contains 2 moles of hydrogen for every mole of carbon and oxygen. The empirical formula for glucose is CH₂O.
The molecular formula of ribose is C₅H₁₀O₅, which can be reduced to the empirical formula CH₂O.
The pair with empirical formula is acetylene, C₂H₂, and benzene, C₆H₆ and
nitrogen dioxide, NO₂, and di nitrogen tetroxide, N₂O₄
Thus, option (A) and (C) are correct.
To learn more about empirical formula, refer to below link:
https://brainly.com/question/14044066
#SPJ2
The volume of a gas was 48 mL when the temperature was 159.6 ºC. If the temperature was initially 4.9 ºC, and there was no change in the pressure, what was the initial volume of the gas?
According to Charles law
[tex]\boxed{\sf \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}}[/tex]
[tex]\\ \sf\longmapsto \dfrac{48}{159.6}=\dfrac{V_2}{4.9}[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{48\times 4.9}{159.6}[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{235.2}{159.6}[/tex]
[tex]\\ \sf\longmapsto V_2=1.4mL[/tex]
Define physical and chemical properties, provide three examples of each, discuss their reversibility, and explain the fundamental differences between them.
Answer:
Physical properties are defined as the properties which can be observed without changing their chemical composition.
For example, color, volume, and molecular weight.
Chemical properties can be defined as, a properties that can be seen only after changing the substance's chemical identity.
For example, reactivity, toxicity, and flammability.
The fundamental differences between physical and chemical properties are as follows:
Chemical properties are related to chemical bonds of the substance, while physical properties are not.
In chemical properties, the chemical identity of substance changes while physical properties does not have any change.
Chemical properties predict the reaction of a substance, while physical properties only describe the appearance of the substance.
Explanation:
An man in Arkansas recently found a 9 carat diamond at Crater of Diamonds State Park. Five carats are equivalent to one gram, so this diamond weighs 1.8 g. Diamond is a crystalline form of the element carbon. How many atoms of carbon are in this 1.8 g diamond
Answer:
The answer is "1.8 g diamond includes 9.03e22 atoms".
Explanation:
Given:
Weight of 9-carat diamond = 1.8 g
[tex]\therefore\\\\[/tex]
weight of 1-mole carbon =12 g
[tex]\because[/tex]
calculating the moles which are available into 18 g carbon weight:
x= Carbon moles weight in 1.8 g
[tex]1 - mol\ C = 12 g\\\\x - mol\ C = 1.8 g\\\\\to x = \frac{(1.8 \ g \times 1\ mol\ C)}{ 12 \ g}\\\\\to x = 0.15\ moles[/tex]
In 1 mole element associated with Avogadro's number that is [tex]6.02 \times 10^{23}\\\\[/tex]
Carbon includes in 1 mol[tex]=6.02 \times 10^{23}\ atoms\\\\[/tex]
0.15 mol of carbon includes:
[tex]= 0.15 \times 6.02 \times 10^{23} = 9.03 \times 10^{22}\ atoms.[/tex]
Using the scientific notation:
0.15 mol of carbon includes: 9.03e22 atoms. So, 1.8 g diamond includes 9.03e22 atoms.
Question 2: thanks!!!
2 Figure 3.1 shows two different forms of carbon, A and B.
A
B
Figure 3.1
a Name the two forms of carbon shown.
Answer:
show the pictures pls specify
What is the pressure of 4 moles of helium in a 50 L tank at 308 K?
Use PV = nRT.
A. 24.64 atm
B. 0.13 atm
O C. 0.51 atm
D. 2.02 atm
Answer:
D
Explanation:
P = Pressure
V = Volume
n = Moles
R = .08206 (because we're using liters)
T = Temperature (as K)
P(50) = (4)(.08206)(308)
P(50) = 101.09792
Divide both sides by 50
P(50)/50 = 101.09792/50
P = 2.0219584
Answer:
[tex]\boxed {\boxed {\sf D. \ 2.02 \ atm}}[/tex]
Explanation:
We are asked to find the pressure of helium gas using the ideal gas law.
[tex]PV= nRT[/tex]
In this formula P is the pressure, V is the volume, n is the number of moles of gas, R is the universal gas constant, and T is the temperature.
The pressure is unknown and we are solving for it. The volume is 50 liters, there are 4 moles of helium gas, the universal gas constant is 0.08206 L *atm/ mol * K, and the temperature is 308 Kelvin.
[tex]\bullet \ V= 50 \ L \\\bullet \ n= 4 \ mol \\\bullet \ R = \frac {0.08206 \ L * atm}{mol *K}\\\bullet \ T= 308 \ K[/tex]
Substitute these values into the formula.
[tex]P * 50 \ L= 4 \ mol * \frac {0.08206 \ L * atm}{mol *K} * 308 \ K[/tex]
Multiply on the right side. The units of moles (mol) and Kelvin (K) cancel each other out.
[tex]P* 50 \ L = 4 * 0.08206 \ L *atm * 308[/tex]
[tex]P*50 \ L =0.32824 \ L * atm *308[/tex]
[tex]P* 50 \ L = 101.09792 \ L * atm[/tex]
We are solving for the pressure, so we must isolate the variable P. It is being multiplied by 50 liters. The inverse operation of multiplication is division, so divide both sides by 50 L.
[tex]\frac {P* 50 \ L}{50 \ L} = \frac {101.09792 \ L * atm}{50 \ L}[/tex]
[tex]P= \frac {101.09792 \ L * atm}{50 \ L}[/tex]
The units of liters (L) cancel.
[tex]P= \frac{101.09792}{50 } \ atm[/tex]
[tex]P= 2.0219584 \ atm[/tex]
If we round to the nearest hundredth place the 1 in the thousandth place tells us to leave the 2 in the hundredth place.
[tex]P \approx 2.02 \ atm[/tex]
The pressure is approximately 2.02 atmospheres and choice D is correct.
What can form as a result of a chemical reaction?
Answer:
O. compounds
Explanation:
[tex]{ \underline{ \sf{ \blue{christ \: † \: alone}}}}[/tex]
What are the units of molar mass?
A. L/g
B. mol/g
C. g/L
D. g/mol
SUBST
Answer:
D - g/mol
step by step method
step by step of how to convert fahrenheit and celsius to kelvins -5F to kelvins please and thank you
What is the difference between a strong base and a weak base?
A. A strong base is always more concentrated than a weak base,
B. A strong base has a lower Ki than a weak base.
C. A strong base produces more ions in solution than a weak base,
D. A strong base is not as conductive as a weak base.
Answer:
C
Explanation:
solution is an example of______mixtures
Answer:
homogeneous mixture must be the answer
Which of the following type of matter has weakest interparticle force of attraction O a. Liquid water
O b. Iron
O c. Steam
O d. sand
Answer:(b)liquid water is correct option . Because it is a molecular solid and molecular solid has weak interparticle forces of attraction
Explanation:
Which of the following is an example of a chemical change?
A. Sugar breaking down into water and carbon when it is heated
B. A sugar cube being crushed by a spoon
C. Sugar mixing with red food coloring and forming a red solid
D. A sugar cube dissolving in water as the water is stirred
Answer:
I think its sugar breaking down into watee and carbon when it is heated
I HOPE ITS RIGHT IF NOT THEN SORRYHAVE A GREAT DAY :)
Doing my summer school work right now. Please help me pass I don’t want to take chemistry for the third time.
Answer:
13.B 0.15 M KBr
14.C 1 M C²h⁵OH
15.D 0.1 M C⁶H¹²o⁶
16.A 2 K² SO⁴
17.A 2 M K² SO⁴
18.D 0.028 M KBr
19.A 1 M Nal
20.B 0.1 M AICI³
A fixed mass of gas has a volume of 92 cm cube and 3 degrees Celsius. What will be its volume at 18 degrees celsius if the pressure remains constant?
Answer:
94.8454
Explanation:
Let volume be V
Let Temperature be T
V1= 92
T1= 3C but to kelvin 273+3= 300K
V2= ?
T2= 18 C but to kelvin 18+273= 291
[tex] \frac{v1}{t1} = \frac{v2}{t2} [/tex]
[tex] \frac{92}{300} = \frac{v2}{291} [/tex]
[tex]v2 \times 300 = 92 \times 291[/tex]
[tex]v2 = \frac{92 \times 291}{300} [/tex]
[tex]v2 = 94.8454[/tex]
The unit of force newton is a derived unit.Why?
Answer:
Why is the unit of force called a derived unit? That's because the Newton is defined in terms of other units which are more fundamental. One Newton is the force required to accelerate a mass of one kilogramme at the rate of one metre per second squared.
write a balanced chemical equation for the reaction between CO2,H2O, Naclo3 and H2O2
Answer:
2H2O2 + NaClO → NaClO3 + 2H2O
Water is dipolar because:
A. It has two hydrogens, each of which pulls oxygen's electrons and separates the
charges into two areas.
B. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a
slight negative and hydrogens a slight positive charge.
C. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a
slight positive and hydrogens a slight negative charge.
OD. It has two hydrogens, each of which has its own polar area.
Answer:
B. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a slight negative and hydrogens a slight positive charge.
Explanation:
In the water molecule (H2O), an oxygen atom is bonded to two hydrogen atoms. Oxygen atom is much more electronegative (has more attraction for electrons) than hydrogen atom, hence, it pulls electrons from one one of the hydrogen atoms bonded to it making it more negatively charged and the hydrogen atom, more positively charged.
The possession of positive charge (+) and negative charge (-) in the same molecule, caused by uneven flow of electrons is what it means to be DIPOLAR (from dipole). Hence, water is DIPOLAR because oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a slight negative and hydrogens a slight positive charge.
1125 J of energy is used to heat 250 g of iron to 55 °C. The specific heat capacity of iron is 0.45 J/(g·°C).
What was the temperature of the iron before it was heated?
55 °C
55 °C
35 °C
35 °C
45 °C
45 °C
20 °C
Answer:
45 °C.
Explanation:
From the question given above, the following data were obtained:
Heat (Q) = 1125 J
Mass (M) = 250 g
Final temperature (T₂) = 55 °C
Specific heat capacity (C) = 0.45 J/gºC
Initial temperature (T₁) =?
The initial temperature of the iron can be obtained as illustrated below:
Q = MC(T₂ – T₁)
1125 = 250 × 0.45 (55 – T₁)
1125 = 112.5 (55 – T₁)
Divide both side by 112.5
1125/112.5 = 55 – T₁
10 = 55 – T₁
Collect like terms
10 – 55 = –T₁
–45 = –T₁
Multiply through by –1
45 = T₁
T₁ = 45 °C
Therefore, the initial temperature of the iron is 45 °C
b. What chemist finds
out how much nitrogen is in a sample of air
How much heat is added if .0948g of water is increased in temperature by .728 degrees C?
.289 J
.803 J
1.46 J
.055 J
Answer:
0.289J of heat are added
Explanation:
We can relate the change in heat of a substance with its increasing in temperature using the equation:
q = m*ΔT*S
Where Q is change in heat
m is mass of substance (In this case, 0.0948g of water)
ΔT = 0.728°C
S is specific heat (For water, 4.184J/g°C)
Replacing:
q = 0.0948g*0.728°C*4.184J/g°C
q = 0.289J of heat are added
write the electronic configuration of the first 20 element
Please tell me the answer of what is unit?
Answer:
a quantity chosen as a standard in terms of which other quantities may be expressed.
Explanation:
Explanation:
Unit is a standard physical quantity defined and adopted by convention,with other quantity of same kind.
Infrared waves are an example of heat transfer by
A. convection
B. radiation
C. conduction
D. motion of the air
Answer:
convection is my correct answer
Determine the mass of oxygen in a 45.0 g sample of calcium carbonate
Answer:
The mass of oxygen in 45.0 g sample of calcium carbonate is approximately 21.58 g
Explanation:
The chemical formula for calcium carbonate is CaCO₃
The molar mass of CaCO₃ = 100.0869 g/mol
The mass of oxygen in one mole of CaCO₃ = 3 × 15.999 g = 47.997 g
The mass of oxygen in 45.0 g sample of CaCO₃, m, is goven as follows;
m = 45.0/100.0869 × 47.997 g ≈ 21.58 g
The mass of oxygen in 45.0 g sample of calcium carbonate, m ≈ 21.58 g
