Answer:
B, wax melting
Explanation:
When wax melts, the form of matter is the only thing that changes. Wax in this case goes from a solid to a liquid, and this process can be reversed when it cools. Hence labeling it a physical change instead.
What is hydrology?
А. the study of weather patterns throughout the earth
B. the study of oceans and freshwater sources
С. the study of the movement and distribution of water on earth
the study of the movement of air throughout the earth
Answer:
c
Explanation:
Hydrology is the study of the distribution and movement of water both on and below the Earth’s surface, as well as the impact of human activity on water availability and conditions.
chemistry:
plz help me:D
Answer:
1 atom only with the unit u.
Explanation:
The formula mass of a substance is defined as the sum of the atomic masses of all atoms in a formula unit of the particular substance in question.
Thus the correct answer is option A
PLSSS HELP MEE
CH3COOH + Mg
CH3-COOH+MgO
CH3 -COOH + Mg(OH)2
CH3-COOH + MgCO3
Explanation:
CH3COOH + Mg --> Mg(CH3COO)2 + H2
CH3COOH + MgO --> H2O + Mg(CH3COO)2
CH3COOH + Mg(OH)2 --> H2O + (CH3COO)2Mg
CH3COOH + MgCO3 --> (CH3COO)2Mg + CO2 + H2O.
*equations are not balanced.
hope it helps. :)
Which renewable resource gets its direct energy from the sun?
O Geothermal
O Solar
O Hydoelectric
O Eolic
Answer:
Solar
Explanation:
Solar mean sun
Example (Solar Panels)
Answer:
Solar
Explanation:
Solar is a renewable energy that receives direct energy from the sun.
define the word isotope
Answer:
Isotope, one of two or more species of atoms of a chemical element with the same atomic number and position in the periodic table and nearly identical chemical behaviour but with different atomic masses and physical properties.
Answer:
Isotopes are two or more types of atoms with the same atomic number but differing nucleon numbers due to varying numbers of neutrons in their nuclei.
OAmalOHopeO
Cool air over warm water will:
Increase in temperature
Stay the same in temperature
Decrease in temperature
Answer:
Air and Water Temperature Increases
An increase in the air temperature will cause water temperatures to increase as well. ... Lower levels of dissolved oxygen due to the inverse relationship that exists between dissolved oxygen and temperature. As the temperature of the water increases, dissolved oxygen levels decrease.
PLEASE HELP ME!
I need the mass!!
A cube of iron at 20C is placed in contact with a cube of copper at 60C. Which statement describes the initial flow of heat between the cubes?
Answer:
the iron is more condensed then the copper more electricity
What does corona mean?
Answer:
.
Explanation:
What is the purpose of an experimental group?
The purpose of having experimental groups is to have sufficient data to be reasonably sure the relationship between the independent and dependent variable is not due to chance.
Answer:
the purpose of an experimental group are:
to enable the experimental study of one variable at a timeto check a different resultIn a reaction, your actual product had a mass of 13.7 grams. You calculated that you need 29.3 grams to have the reaction go to completion. What is your percent yield?
Answer:
5.0
Explanation:
A 21.5 L sample of gas at 107 kPa has a temperature of 27.2 °C. What is the pressure of the gas
if it is transferred to a 32.6L container at 44.1 °C?
Answer:
The right answer is "74.516 kPa".
Explanation:
The given values are:
V₁ = 21.5 L
V₂ = 32.6L
P₁ = 107 kPa
T₁ =27.2°C+273
T₂ = 44.1 °C+273
As we know,
⇒ [tex]\frac{P_1V_1}{T_1}= \frac{P_2V_2}{T_2}[/tex]
then,
⇒ [tex]P_2=\frac{P_1V_1T_2}{T_1V_2}[/tex]
On substituting the given values, we get
⇒ [tex]=\frac{107\times 21.5\times (44.1+273)}{(27.2+273)\times 32.6}[/tex]
⇒ [tex]=\frac{107\times 21.5\times 317}{300.2\times 32.6}[/tex]
⇒ [tex]=\frac{729258.5}{9786.52}[/tex]
⇒ [tex]=74.516 \ kPa[/tex]
Which object orbits Earth in both the Earth-centered (geocentric) and Sun-centered (heliocentric) models of our solar system?
A) the Moon
B) the Sun
C) Venus
D) Polaris
Answer:
the moon
Explanation:
Explain the effect of change in concentration of a system in Equilibrium with at least one example.
Explanation:
If the concentration of a substance is changed, the equilibrium will shift to minimise the effect of that change. If the concentration of a reactant is increased the equilibrium will shift in the direction of the reaction that uses the reactants, so that the reactant concentration decreases. For example, decreased volume and therefore increased concentration of both reactants and products for the following reaction at equilibrium will shift the system toward more products.
Chemistry test!!! no fake answers please and if you can explain then do it because I need all the help I can get!
Answer:
(−ΔH°1)+12(−ΔH°2)+(ΔH°3)+(ΔH°4)
I hope this helps you out!! :)
Hydrogen and oxygen react to form a water which statement best describes the reactants and product at equilibrium
Answer:
H2 (g) + I2 (g) = 2HI (g)
Explanation:
Forward reaction:H2(g)+I2(g)→2HI(g)
Reverse reaction:2HI(g)→H2(g)+I2(g)
pls complete the table with the correct answer
Answer:
The correct answer is :
Natural fibres: these fibers are found naturally in the environment such as cotton, hemp or wool, all are made naturally found fibers.
sr. no. name type
1 Cotton natural
2 Linen natural
3 Silk natural
4 Wool natural
5. Hemp natural
Artificial fibres: made from the polymerization of their monomer unit for example polyester made from coal and petroleum products.
sr. no. name type
1 Polyester artificial
2 Rayon artificial
3 Spandex artificial
4 Acrylic artificial
5. microfibers artificial
The Davis Mountains in West Texas were once taller than they are now. Which of the following forces most likely caused the mountains to become shorter over time?
A. Weathering and erosion only
B. Chemical and mechanical weathering only
C. Erosion and deposition only
D. Weathering, erosion, and deposition
*Please don't put unhelpful answers, i have been stuck on this question for the past few days. Thank you!
10 POINTS
What is used to measure the volume of a solid with an irregular shape? O A. Gas displacement O B. Liquid displacement O C. Plasma displacement O D. Solid displacement
Answer:
Because many objects are not regularly shaped their volume cannot be determined using a volume formula. The volume of these objects can be found by water displacement. A volume of water sufficient to cover the object is placed in a graduated cylinder and the volume read. The object is added to the cylinder and the volume read again. The difference between the two volumes is the volume of the object. This method is demonstrated using the same battery used above.
Explanation:
Help ASAP
3. Components in a heterogeneous mixture are not in the same phase or the composition of the mixture is
a) uniform
b) transparent
c) uneven
Answer:
c
Explanation:
A certain gas has a volume of 500.0 mL at 77.0°C and 600KPa. Calculate the temperature if the volume decreased to 400.0 mL and the pressure is increased to 760Kpa and assume the number of moles does not change.
Answer:
354.67K
Explanation:
Applying
P₁V₁/T₁ = P₂V₂/T₂................. Equation 1
Where Where P₁ = initial pressure, T₁ = Initial temperature, V₁ = Initial Volume, P₂ = Final pressure, V₂ = Final Volume, T₂ = Final Temperature.
From the question, we are ask to look for the final temperature,
Therefore we make T₂ the subject of the equation
T₂ = P₂V₂T₁/P₁V₁............. Equation 2
Given: P₁ = 600 kPa, V₁ = 500 mL, T₁ = 77 °C = (273+77) = 350 K, P₂ = 760 kPa, V₂ = 400.0 mL
Substitute these values into equation 2
T₂ = (760×400×350)/(600×500)
T₂ = 354.67 K
2C(s) + 2H2(g) → C2H4(g): ΔH = +52.4 kJ/mol
Which statement about this reaction is correct? (3 points)
De una misma estación salen, en el mismo instante, dos trenes, con velocidades constantes de 72 y 90 [km/h]. ¿Qué distancia separa ambos trenes luego de 2 horas de viaje si se mueven en la misma dirección ... a) ... Y en el mismo sentido de circulación?
Answer:
144 km y 180 km respectivamente.
Explanation:
¡Hola!
En este caso, dado que tenemos dos trenes con velocidades diferentes, es posible multiplicar la velocidad de cada tren por el tiempo común, con el fin the hallar la distance recorrida; es de entender, que a mayor velocidad, mayor distance ha de recorrer el tren:
[tex]d_1=72km/h*2h=144km\\\\d_2=90km/h*2h=180km[/tex]
Así, entendemos que el tren número 1 recorre 144 kilómetros, mientras que el tren número 2, 180 kilómetros.
¡Saludos!
Once a product is ready to be sold, engineers must explain their ideas to people who will bring the product to consumers.
Please select the best answer from the choices provided
ОТ
OF
Answer:
ot
Explanation:
there is no choices
Answer:
Advertise
Explanation:
once a product is ready to be sold, engineers explain their ideas to marketing people, who will advertise the product.
Which of the following ions will form the weakest bond with Na+?
Br^-
F^-
CI^-
I^-
Answer:
Iodide ion, I- will form the weakest bond with sodium ion, Na+
Explanation:
Electronegativity is the ability with which a neutral atom attracts electrons to itself.
The electronegativity of the halogens decrease on going down the group among the halogens. This is is because on going down the group, the atomic size as well as ionic size of the atoms in the group increases. This increase decreases the effect of the attraction of the positive nucleus on the electrons. Thus, valence electrons can be more readily removed.
The transfer of electrons from metallic sodiummto a halogen results in annionic bond between the two atoms. The strength of the ionic bond decreases on going down the group due to decrease in electronegativity. Thus, iodide ion, I-, which is the least electronegative among the given options will form the weakest bond with Na+.
Initially a NaOH solution was standardized by titration with a sample of potassium hydrogen phthalate, KHC8H4O4, a monoprotic acid often used as a primary standard. A sample of pure KHC8H4O4 weighing 1.518 grams was dissolved in water and titrated with the NaOH solution. To reach the equivalence point, 26.90 milliliters of base was required. Calculate the molarity o
Answer:
0.2763M NaOH
Explanation:
Based on the reaction of hydrogen phtalate, KHP, with sodium hydroxide, NaOH:
KHP + NaOH → KNaP + H₂O
1 mole of KHP reacts per mole of NaOH.
In the equivalence point, the moles of NaOH added = Moles of KHP that were dissolved.
Thus, to solve this question, we must find the moles of KHP = Moles NaOH. With the moles and the volume of NaOH required to reach the equivalence point we can find molarity of NaOH solution:
Moles KHP = Moles NaOH (Molar mass KHP = 204.22g/mol):
1.518g * (1mol / 204.22g) = 7.433x10⁻³ moles NaOH
In 26.90mL = 0.0269L:
7.433x10⁻³ moles NaOH / 0.02690L
0.2763M NaOHyou may not want to wear a black shirt in the hot summer because light is
Answer:
The outer layer of fabric does get hotter because the black color absorbs more heat. And that heat doesn't get transmitted to the skin because of the thick fabric. But thin black clothing transmits that heat to the skin, making a person hotter.
Explanation:
✓ What kind of carbon storages would be the least affected by humans?
Answer:
trio
Explanation:
What are the characteristic property's of metals such as malleability and high conductivity are due to ?
Answer:
Metallic Bonding
Explanation:
Conductivity occurs when electrons or ions are free moving. The conductivity in metals is due to electrons being delocalized in a sea of electrons. Metals contain metallic bonding which allows the electrons to freely move.
Malleability happens when adjacent layers of positive ions move relative to one another while being in contact with the sea of electrons from the metallic bonding.
Identify the decay mode
Please answer asap no explanation needed
(Look at picture)
Answer:
1921 :3 espero y te ayude crack