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jarptica [38.1K]

3 years ago

5

What major invention led to the cell theory?

2 answers:

RideAnS [48]3 years ago

4 0

Answer:

microscope

Explanation:

As the cells very too tiny to be seen by our naked eyes, so invention of microscope led to cell theory

My name is Ann [436]3 years ago

3 0

Answer:

the microscope

Explanation:

Robert Hooke was the first to use it

You might be interested in

Which chromosome cause apples to be a `paticular` color?

vlada-n [284]

It's an allele not a chromosome

7 0

4 years ago

A materials scientist has created an alloy containing aluminum, copper, and zinc, and wants to determine the percent composition

liubo4ka [24]

Answer:

0.8749 grams of hydrogen gas was formed from the reaction.

Explanation:

P = Pressure of hydrogen gad= 744 Torr = 0.98 atm

(1 atm = 760 Torr)

V = Volume of hydrogen gas= 11 L

n = number of moles of hydrogen gas= ?

R = Gas constant = 0.0821 L.atm/mol.K

T = Temperature of vapor = 27.0 °C = 300.15 K

Putting values in above equation, we get:

Using an ideal gas equation:

$PV=nRT$

$n=\frac{PV}{RT}=\frac{0.98 atm\times 11 L}{0.0821 L atm/mol K\times 300.15 K}$

n = 0.4374 moles

Mass of 0.4374 moles of hydrogen gas:

0.4374 mol × 2 g/mol = 0.8749 g

0.8749 grams of hydrogen gas was formed from the reaction.

7 0

4 years ago

- How many moles of H2O are required to react to form 2.5 grams of CH ?

abruzzese [7]

Answer:

0.312 moles of H2O

Explanation:

no. of moles of ch4= mass ÷ molar mass

=2.5 ÷ 16.04

=0.156 moles of ch4

According to balanced chemical equation

CH4 : H2O

1 mole : 2 moles

0.156 moles : x moles

by cross multiplication

x= (0.156x2) ÷ 1

= 0.312 moles of H2O

7 0

4 years ago

In a study of the following reaction at 1200 K it was observed that when the equilibrium partial pressure of water vapor is 15.0

sp2606 [1]

Answer:

The value of $K_p$ for this reaction at 1200 K is 4.066.

Explanation:

Partial pressure of water vapor at equilibrium = $p^o_{H_2O}=15.0 Torr$

Partial pressure of hydrogen gas at equilibrium = $p^o_{H_2}=?$

Total pressure of the system at equilibrium P = 36.3 Torr

Applying Dalton's law of partial pressure to determine the partial pressure of hydrogen gas at equilibrium:

$P=p^o_{H_2O}+p^o_{H_2}$

$p^o_{H_2}=P-p^o_{H_2O}=36.3 Torr- 15.0 Torr = 21.3 Torr$

$3 Fe(s) 4 H_2O(g)\rightleftharpoons Fe_3O_4(s) 4 H_2(g)$

The expression of $K_p$ is given by:

$K_p=\frac{(p^o_{H_2})^4}{(p^o_{H_2O})^4}$

$K_p=\frac{(21.3 Torr)^4}{(15.0 Torr)^4}=4.066$

The value of $K_p$ for this reaction at 1200 K is 4.066.

6 0

3 years ago

Through the complete electrolysis of a sample of pure water, a student collects 14.0 grams of hydrogen gas and 112.0 grams of ox

Vadim26 [7]

Answer:

126.0g of water were initially present

Explanation:

The electrolysis of water occurs as follows:

2H₂O(l) ⇄ 2H₂(g) + O₂(g)

<em>Where 2 moles of water produce 2 moles of hydrogen and 1 mole of oxygen.</em>

<em />

To find the mass of water we need to determine moles of oxygen and hydrogen, thus:

<em>Moles Hydrogen:</em>

14.0g H₂ ₓ (1mol / 2g H₂) = 7 moles H₂

<em>Moles Oxygen:</em>

112.0g O₂ ₓ (1mol / 32g) = 3.5 moles O₂

Based on the chemical equation, the moles of water initially present were 7 moles (That produce 7 moles H₂ and 3.5 moles O₂). The mass of 7 moles of H₂O is:

7 moles H₂O * (18g / mol) =

<h3>126.0g of water were initially present</h3>

6 0

4 years ago