How did technology impact the development of the cell theory?

Abigail obtained 18.9 grams of calcium carbonate after performing a reaction. From her calculations, she knew she should have ob

zysi [14]

Answer:Percent error= 90.9%

Explanation:

Percent error or percentage error is defined as the percentage of the difference between a measured value usually from an experiment and an exact value in comparison to the exact number.

its formula is thus

Percent error = experimental value - exact or actual value /exact value x 100

=(18.9 - 9.9 /9.9 ) x 100= 9/9.9) x 100

0.909 x 100 = 90.90 = 90.9%

5 0

4 years ago

If 2.06 mL of seawater contains about 0.446 moles of gold, how many atoms of gold are in that volume of seawater?

Alborosie

Answer:

2.69 x 10²³ atoms

Explanation:

Given parameters:

Volume of sea water = 2.06mL

number of moles of gold = 0.446moles

unknown:

Number of atoms in the sea water

Solution:

The mole is a convenient unit of measuring quantities of particles. In a mole we have 6.02 x 10²³particles.

The mole can be defined as the amount of a substance contained in Avogadro's number of particles which is 6.02 x 10²³particles.

Here, the particles we want to determine is the number of atoms:

Number of atoms is given as:

Number of gold atoms = number of moles of gold x 6.02 x 10²³

Number of gold atoms = 0.446 x 6.02 x 10²³ = 2.69 x 10²³ atoms

5 0

4 years ago

I'll be giving out brainliest to whoever chooses more than one!!!

Kruka [31]

I think it might be B, and A

8 0

3 years ago

Consider the general reaction: 2 A + b B → c C and the following average rate data over a specific time period \Delta t: - \frac

lawyer [7]

Answer:

c = 4

Explanation:

In general, for the reaction

a A + b B ⇒ c C + d D

the rate is given by:

rate = - 1/a ΔA/Δt = - 1/b ΔB/Δt = + 1/c ΔC/Δt = + 1/d ΔD/Δt

this is done so as to express the rate in a standarized way which is the same to all the reactants and products irrespective of their stoichiometric coefficients.

For this question in particular we know the coefficient of A and need to determine the coefficient c.

- 1/2 ΔA/Δt = + 1/c ΔC/Δt

- 1/2 (-0.0080 ) = + 1/c ( 0.0160 mol L⁻¹s⁻¹ )

0.0040 mol L⁻¹s⁻¹ c = 0.0160 mol L⁻¹s⁻¹

∴ c = 0.0160 / 0.0040 = 4

7 0

3 years ago

Determine the total pressure of all gases (at STP) formed when 50.0 mL of TNT (C3H5(NO3)3, , molar mass = 227.10 g/mol) reacts a

bija089 [108]

Answer:

Total pressure is 1189 atm

Explanation:

This is the reaction:

4C₃H₅(NO₃)₃ → 6N₂ + O₂ + 12CO₂ + 10H₂O

As we have the volume of TNT, we must know the density to find out the mass and then, apply molar mass to calculate mole.

TNT density = 1.654 g/mL

Density = mass / volume

1.654 g/mL = TNT mass / 50mL

1.654 g/mL . 50mL = TNT mass → 82.7 g

Mass / Molar mass = Mol → 82.7 g / 227.1 g/m = 0.364 mole

Now, we can calculate all the mole for the formed gases.

4 mole of TNT produce 6 mole N₂ ___ 1 mol O₂ __ 12 mole dioxide __ 10 mole of water

0.364 mole of TNT will produce:

- (0.364 . 6) /4 = 0.546 mole of produced nitrogen

- (0.364 . 1) /4 = 0.091 mole of produced oxygen

- (0.364 . 12) /4 = 1.092 mole of produced dioxide

- (0.364 . 10) /4 = 0.91 mole of produced vapour of water.

Total mole = 0.564 + 0.091 + 1.092 + 0.91 = 2.657 mole

Let's apply the Ideal Gases Law to find the total pressure, at STP

In STP, pressure is 1 atm for 1 mole at 273K, in a volume of 22.4 mL

But we have a volume of 50mL, and we have 2.657 total mole

Don't forget to convert 50 mL to L, cause the units for R

50 mL = 0.050L

P . 0.050L = 2.657 mol . 0.082L.atm/mol.K . 273K

P = (2.657 mol . 0.082L.atm/mol.K . 273K) / 0.050L

P = 1189 atm

3 0

3 years ago