How much thermal energy must be added to a 87.5 g sample of ice at -25oC completely melt the entire sample? As part of your work, sketch a labelled heating curve. Circle the portion of the curve that is the focus of this question.

Answer:

d is the correct answer

Explanation:

Answer:

The columns of the periodic table are called groups. Members of the same group in the table have the same number of electrons in the outermost shells of their atoms and form bonds of the same type. The horizontal rows are called periods.

Answer:

4,1,4

Explanation:

Balancing a synthesis equation

N2+3H2-->2NH3

first we find the number of nitrogen moles

the molar mass for N2 is 14+14=28g/mole

to find the number of moles we divide the mass by the molar mass

n=400/28=14.28 moles

for 1 mole of N2 we use 3 moles of H2, therefore for 14.28 moles of N2 we use 14.28*3=42.84 moles ofH2

to find the mass of H2 we multiply the number of moles by the molar mass

the molar mass of H2 is 2g/mole

2*42.84=85.68g of H2

Answer:

C

Explanation:

75 mile shallow flat area just off coastlines

Answer:

B) we will convert the 10 g of NaCl into moles.

Explanation:

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles of solute / L of solution

we will convert the 10 g of NaCl into moles.

Number of moles of NaCl:

Number of moles = mass/molar mass

Number of moles = 10 g/ 58.44 gmol

Number of moles = 0.17 mol

1 Kg = 1 L

Molarity = 0.17 mol / 2 L

Molarity = 0.085 mol/L

Molarity = 0.085 M

Answer:

B. Convert the 10g of NaCl to moles of NaCl

do you have some examples or options to answer ?

Answer:

Hi! Think of it like this:

You and your family are going to go on a vaction for the holidays, to south america or somewhere else. You´re near the equator so it will be warm. If you were to move there, you might pull out the swimsiutes because most of the time, its useally warm and sunny. They dont really get cold weather. They will have a nice and warm christmas.

Answer:

D.

Explanation:

This is the correct equation for photosynthesis! :)

Answer: x108(5.03x−42.6)

Explanation: Factor 5.03x109−42.6x108

5.03x109−42.6x108

=x108(5.03x−42.6)

Answer:

An acid is the specie which can donate a proton.

Explanation:

Bronsted lower acid:

An acid is the specie which can donate a proton.

Bronsted lower base:

A base is the specie that can accept the proton.

For example:

HCl + NH₃     →       NH₄⁺ + Cl⁻

Here in this reaction HCl is act an acid because it donate the proton while NH₃ is Bronsted lower base because it accept the proton.

Bronsted lowery acid = proton donor

Bronsted lowery base = proton accepter

Answer:

the molecules in the reactants interact to form new substances.

Explanation:

Answer:

Aluminium + oxygen = almininum oxide

Hope it helps!! Please make me brainliest...

Merry Christmas good day

Answer:

Normality of KOH = 0.1062 N

Note: The given question is not clearly stated. A related question below is answered and explained;

What is the NORMALITY of a solution of KOH if 45.18 mL are required to neutralize 0.3g of pure oxalic acid H2C2O4 . 2H2O?

Explanation:

Equation of the reaction: 2KOH + H₂C₂O₄.2H₂O --> K₂C₂O₄ + 4H₂O

molar mass 0f KOH = 56 g/mol; molar mass of H₂C₂O₄.2H₂O = 126 g/mol

Number of moles of in 0.3 g of H₂C₂O₄.2H₂O = mass/molar mass

number of moles = 0.3 g / 126 g/mol = 0.0024 moles

From the equation of reaction, 2 moles of KOH are required to neutralize 1 mole of H₂C₂O₄.2H₂O

Number of moles of KOH required to neutralize 0.0024 moles of H₂C₂O₄.2H₂O = 2 * 0.0024 = 0.0048 moles

Molar concentration of 45.18 mL solution of KOH containing 0.0048 moles of  KOH = number of moles/volume (L)

molarity of KOH solution = (0.0048/45.18 mL) * (1000 mL/1 L) = 0.1062 mol/L

Normality = n * molarity

where is the number of moles of OH⁻ ions produces from  mole of KOH = 1

Normality of KOH = 1 * 0.1062

Normality of KOH = 0.1062 N

Answer:

Multicellular Organisms.

Explanation:

Hi

Answer:

b.

Explanation:

As the ozone layer is essential for nullifying the rays of the sun, without it there would be much more UV radiation.

Answer:

A)The total number of protons plus neutrons= Weight of an atom

Answer:

A solubility chart with a list of ions

Explanation:

when mixed with other ions, they can become precipitates or remain aqueous. The following chart shows the solubility of multiple independent and various compounds, in water, at a pressure of 1 atm and at room temperature (approx. 293.15 K).

Answer:

it tells which compounds will dissolve in water

Explanation:

a p e x :)

Answer:

8.117grams

Explanation:

its obtained from Q=MCT where

Q-HEAT REQUIRED

C-SPECIFIC HEAT CAPACITY OF WATER

M-MASS OF WATER

T-TEMPERATURE CHANGE(100C-34C)

Number of moles = 78.41

The mole is the number of particles(molecules, atoms, ions) contained in a substance  

1 mol = 6.02.10²³ particles

Can be formulated

N=n x No

N = number of particles

n = mol

No = Avogadro's = 6.02.10²³

4.72 x 10²⁵ atoms of a substance, then moles :

[tex]\tt n=\dfrac{N}{No}\\\\n=\dfrac{4.72\times 10^{25}}{6.02\times 10^{23}}\\\\n=78.41[/tex]

Answer:

2 % de cafe, 20% de azucar, 100% de agua.

Explanation:

Un clásico problema de soluciones:

- Nuestros solutos son 4 g de cafe y 20 g de azúcar.

- en 200 mL de agua

Podemos asumir que los 200mL es el volumen de solución.

%m/v es un tipo de concentración que señala los gramos de soluto en 100 mL de solución.

% m/v de cafe →  (4/200) . 100 = 2 %

% m/v de azucar →  (20/200) . 100 = 20 %

Si tomamos al agua como sustancia que forma parte de la solución sería

(200/200) . 100 = 100 %

Lo que podríamos leer 100 g de agua en 100 mL de agua, dado que la densidad del agua es 1 g/mL

Answer:

Mass = 12.27 g

Explanation:

Given data:

Mass of NaCl are required = ?

Volume of AgNO₃ = 346 mL (346 mL× 1L/ 1000 mL = 0.346 L)

Molarity of AgNO₃ = 0.607 M

Solution:

Chemical equation:

NaCl  + AgNO₃     →    NaNO₃ + AgCl

Number of moles of AgNO₃:

Molarity = number of moles / volume in L

0.607 M = number of moles / 0.346 L

number of moles =  0.607 M × 0.346 L

number of moles =  0.21 mol

now we will compare the moles of NaCl and AgNO₃.

                       AgNO₃         :          NaCl        

                           1                :            1

                       0.21              :            0.21

Mass of NaCl:

Mass = number of moles × molar mass

Mass = 0.21 mol × 58.44 g/mol

Mass = 12.27 g

Answer:

latent heat of condensation will have the same absolute value as the latent heat of vaporization. The latent heat of condensation will be negative. The latent heat of condensation is a characteristic property that can be used to identify a substance.

Explanation:

Answer:

energy absorbed or released by a substance during a change in its physical state (phase) that occurs without changing its temperature.

Explanation:

Answer:

1s^2   2s^2   2p^6    3s^2    3p^6    4s^2    3d^10   4p^6    5s^2    4d^2

Explanation:

Answer:

The carbon dioxide molecule is linear and centrosymmetric at equilibrium. The carbon–oxygen bond length is 116.3 pm, noticeably shorter than the bond length of a C–O single bond and even shorter than most other C–O multiply-bonded functional groups. Since it is centrosymmetric, the molecule has no electrical dipole.

Explanation:

Answer:

The carbon dioxide molecule is linear and centrosymmetric at equilibrium. The carbon–oxygen bond length is 116.3 pm, noticeably shorter than the bond length of a C–O single bond and even shorter than most other C–O multiply-bonded functional groups. Since it is centrosymmetric, the molecule has no electrical dipole.

Carbon dioxide | CO2 | CID 280 - structure, chemical names, physical and chemical ... It is a one-carbon compound, a gas molecular entity and a carbon oxide. ... Physical and Thermodynamic Properties of Pure Chemicals Data Compilation. ... These actions are exploited clinically in the use of hyperventilation to diminish ...

Molecular Formula: CO2

PubChem CID: 280

Molecular Weight: 44.009 g/mol

Chemical Safety: Laboratory Chemical Safety

Answer:

At the plate boundary, there would be a divergent boundary where we can see a mid ocean ridge and a gap. We would be able to see the mantle because there would be a fissure from where magma will rise and solidify.    

Explanation:

Under the South American plate and African plate, there are currents that cause a divergent boundary. They create this boundary since they pull the tectonic plates apart, causing a mid-ocean ridge with an opening that allows the rising of the magma that was underneath. Once that the magma is out, it solidifies, and the currents will try to create another ridge to repeat the process.

When the plates are apart, the mantle that is beneath is exposed, and we can see the magma.