All categories

2 years ago

Calculate the amount of heat needed to raise the temperature of 4 ml of water from 10C to 30C

Chemistry

1 answer:

Over [174]2 years ago

4 0

Answer:

$Q=80cal$

Explanation:

Hello,

In this case, the relationship between heat, mass, specific heat and change in temperature is understood by:

$Q=mCp(T_2-T_1)$

In this case, since the involved substance is water, whose specific heat is 1 cal/(g°C), we compute the heat 4 mL of water need to rise the temperature from 10 °C to 30 °C as shown below:

$Q=4mL*\frac{1g}{1mL}*1\frac{cal}{g\°C}*(30\°C-10\°C)\\ \\Q=80cal$

Best regards.

You might be interested in

Calculate Ecell at 80 ºC for a voltaic cell based on the following redox reaction: H2(g, 1.25 atm) + 2AgCl(s) → 2Ag(s) + 2H+(aq,

iris [78.8K]

Answer:

Ecell = +0.25V

Explanation:

the half-cell reactions for a voltanic cell

cathode(reduction): 2H⁺(aq) + 2e⁻ ------- H₂(g)

anode(oxidation): 2AgCl(s) ------- 2Ag⁺(aq) + 2Cl⁻ + 2e⁻

we have the standard cell potential E⁺cell = 0.18V at 80C respectively

Q = [H⁺]/[Cl⁻]

sub for [H+] = 0.10M and [Cl-] = 1.5M

Q= 0.1M/1.5M

Q = 0.067

Ecell = E⁺cell - $\frac{0.059}{n}$ logQ

= 0.18 - $\frac{0.056}{1}$ log 0.067

0.18- 0.059(-1.174)

Ecell = +0.25V

6 0

3 years ago

How does concentration affect our daily lives in science?

statuscvo [17]

1. <em>Increasing the concentration of one or more reactants will often increase the rate of reaction. This occurs because a higher concentration of a reactant will lead to more collisions of that reactant in a specific time period. </em>

<em>2. Physical state of the reactants and surface area.</em>

8 0

3 years ago

Imagine that Ana has a block made of pure gold. If she cuts this block into two equal pieces, pick the statement that best descr

dimaraw [331]

Answer : The correct statement is:

The density of each piece is the same as that of the original block.

Explanation :

Intensive property : It is defined as a property of substance which does not change as the amount of substance changes.

Examples: Temperature, refractive index, density, hardness, etc.

According to question, if Ana has a block made of pure gold and she cuts this block into two equal pieces then the density of each piece is the same as that of the original block because density is an intensive property that does not changes until and unless material is changed.

That means density remains same as that of the original piece.

Hence, the correct statement is the density of each piece is the same as that of the original block.

6 0

3 years ago

Olive oil has a density of 0.92 g/mL. How much would 1 liter of olive oil weigh in grams?

svp [43]

Dimension analysis is to be used to solve this problem. First convert 1L to milliliters. That is equivalent to 1000 ml. Then by dimension analysis, multiply the volume ( 1000ml) to the density of oil (0.92 g/ml) resulting to the answer: 920 grams.

4 0

3 years ago

A sample of table sugar (sucrose, C12H22O11) has a mass of 1.202 g.

Archy [21]

Answer:

a) 0.003512 moles

b) Moles C= 0.04214 moles carbon

Moles H = 0.07726 moles hydrogen

Moles O = 0.03863 moles of oxygen

c) C atoms = 2.54 *10^22 carbon atoms

H atoms = 4.65 *10^22 hydrogen atoms

O atoms = 2.33 *10^22 oxygen atom

Explanation:

Step 1: Data given

Mass of sucrose = 1.202 grams

Molar mass of sucrose = 342.3 g/mol

Step 2: Calculate moles of sucrose

Moles sucrose = Mass sucrose / molar mass sucrose

Moles sucrose = 1.202 grams / 342.3 g/mol

Moles sucrose = 0.003512 moles

Step 3: Calculate moles of each element

For 1 mol of C12H22O11 we have 12 moles of carbon, 22 moles of hydrogen and 11 moles of oxygen

Moles C: 12*0.003512 = 0.04214 moles carbon

Moles H: 22* 0.003512 = 0.07726 moles hydrogen

Moles O: 11* 0.003512 = 0.03863 moles of oxygen

Step 4: Calculate the number of atoms

C atoms = 6.022 *10^23 / mol * 0.04214 moles = 2.54 *10^22 atoms carbon

H atoms = 6.022 * 10^23 / mol * 0.07726 moles = 4.65 *10^22 atoms H

O atoms = 6.022 * 10^23 / mol * 0.03863 moles = 2.33 *10^22 atoms O

0.003512 moles of sucrose containse 6.022 *10^23 * 0.003512 = 2.11 * 10^21 sucrose molecules

7 0

3 years ago