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2 years ago

I need help with question 2 I will brainliest you if I’m able to

Chemistry

2 answers:

erik [133]2 years ago

4 0

Answer:

Blank 1: Microscope

Blank 2: Cells

vfiekz [6]2 years ago

3 0

Answer: (answers are in bold)

Because of the invention of the microscope, we know that all organisms are made of small living creatures called cells.

Explanation:

Well the statement explains itself; I'll explain the invention of the microscope.

No one really knows who invented the simple microscope, but the compound microscope was invented c. 1590 by Dutch lens-maker Zacharias Janssen. He used it to magnify object to about 10x their original size. Anton von Leeuwenhoek made even better ones; those had up to 275x magnification.

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What happens to most of the Energy that an organism gets from consuming food? Help please

kobusy [5.1K]

It’s the second answer. “it gets used for metabolic process & released as heat” i think.

7 0

2 years ago

Read 2 more answers

How would one go about solving this?? Thank you.

Marta_Voda [28]

Answer:

5.66g/ml

Explanation:

Mass of Metal Slug, m = 25.17g

Volume of container (flask), v = 59.7ml

Mass of Methanol, M = 43.7g with density, d = 0.791g/ml

Therefore,

Volume of Methanol = M/d = 43.7 / 0.791 = 55.25ml

Volume of Metal slug in the flask = v - V = 59.7 - 55.25 = 4.45ml

Density of Metal slug = mass of metal slug / volume of metal slug

= 25.17 / 4.45 = 5.66g/ml

7 0

3 years ago

1. The heat absorbed when ice melts can

zmey [24]

4 a joule is the answer

3 0

3 years ago

The solubility of CO2 in water is 0.161 g/100 mL at 20oC and a partial pressure of CO2 of 760 mmHg. What partial pressure of CO2

Schach [20]

Answer: The partial pressure of carbon dioxide having solubility 0.886g/100mL is 4182.4 mmHg

Explanation:

Henry's law states that the amount of gas dissolved or molar solubility of gas is directly proportional to the partial pressure of the liquid.

The equation given by Henry's law is:

$C_{CO_2}=K_H\times p_{CO_2}$ ......(1)

where,

$C_{CO_2$ = solubility of carbon dioxide in water = 0.161 g/100 mL

$K_H$ = Henry's constant = ?

$p_{CO_2}$ = partial pressure of carbon dioxide = 760 mmHg

Putting values in equation 1, we get:

$760mmHg=K_H\times 0.161g/100mL\\\\K_H=\frac{760mmHg}{0.161g/100mL}=4720.5g.mmHg/100mL$

Now, calculating the pressure of carbon dioxide using equation 1, we get:

$C_{CO_2$ = solubility of carbon dioxide in water = 0.886 g/100 mL

$K_H$ = Henry's constant = 4720.5 g.mmHg/100 mL

$p_{CO_2}$ = partial pressure of carbon dioxide = ?

Putting values in equation 1, we get:

$p_{CO_2}=4720.5g.mmHg/100mL\times 0.886g/100mL=4182.4mmHg$

Hence, the partial pressure of carbon dioxide having solubility 0.886g/100mL is 4182.4 mmHg

4 0

3 years ago

Potassium nitrate has a lattice energy of -163.8 kcal/mol and a heat of hydration of -155.5 kcal/mol.

Brut [27]

Answer:

293.99 g

0.293 Kg

Explanation:

Given data:

Lattice energy of Potassium nitrate (KNO3) = -163.8 kcal/mol

Heat of hydration of KNO3 = -155.5 kcal/mol

Heat to absorb by KNO3 = 101kJ

To find:

Mass of KNO3 to dissolve in water = ?

Solution:

Heat of solution = Hydration energy - Lattice energy

= -155.5 -(-163.8)

= 8.3 kcal/mol

We already know,

1 kcal/mol = 4.184 kJ/mole

Therefore,

= 4.184 kJ/mol x 8.3 kcal/mol

= 34.73 kJ/mol

Now, 34.73 kJ of heat is absorbed when 1 mole of KNO3 is dissolved in water.

For 101 kJ of heat would be

= 101/34.73

= 2.908 moles of KNO3

Molar mass of KNO3 = 101.1 g/mole

Mass of KNO3 = Molar mass x moles

= 101.1 g/mole x 2.908

= 293.99 g

= 0.293 kg

293.99 g potassium nitrate has to dissolve in water to absorb 101 kJ of heat.

4 0

3 years ago