All categories

2 years ago

Please help me I will give you the brain thing with extra points if you help me, please. I need to get this right. 8/10

Chemistry

2 answers:

Wewaii [24]2 years ago

8 0

Answer:

40 km

Explanation:

I learned this in the 8th grade..

8_murik_8 [283]2 years ago

5 0

Answer:

C) 40km/hr

Explanation:

1 hour= 60 min

30 times 2= 60

20 times 2=40

40km/60 min

40km/hr

You might be interested in

I need the answers of these

Anni [7]

Answer:

Hope this helps :D

Explanation:

Metal: Aluminum and Copper

Non-Metal: Hydrogen and Flourine

Acid: Sulfuric Acid and Phosphoric Acid

Alkali Metals: Hydrogen and Lithium

Compounds: Water and Carbon Dioxide

Elements: Carbon and Oxygen

4 0

1 year ago

based on table s an atom of which elements has the weakest attraction for electrons in a chemical bond

Norma-Jean [14]

It seems that you have missed the necessary table for us to answer this question, so I had to look for it. Anyway, here is the answer. Based on Table S, an atom of the element POLONIUM has the weakest attraction for electrons in a chemical bond. Hope this answers your question.

5 0

3 years ago

Consider the reaction below for which K = 78.2 atm-1. A(g) + B(g) ↔ C(g) Assume that 0.386 mol C(g) is placed in the cylinder re

borishaifa [10]

Answer:

1.65 L

Explanation:

The equation for the reaction is given as:

A + B ⇄ C

where;

numbers of moles = 0.386 mol C (g)

Volume = 7.29 L

Molar concentration of C = $\frac{0.386}{7.29}$

= 0.053 M

A + B ⇄ C

Initial 0 0 0.530

Change +x +x - x

Equilibrium x x (0.0530 - x)

$K = \frac{[C]}{[A][B]}$

where

K is given as ; 78.2 atm-1.

So, we have:

$78.2=\frac{[0.0530-x]}{[x][x]}$

$78.2= \frac{(0.0530-x)}{(x^2)}$

$78.2x^2= 0.0530-x$

$78.2x^2+x-0.0530=0$

Using quadratic formula;

$\frac{-b+/-\sqrt{b^2-4ac} }{2a}$

where; a = 78.2 ; b = 1 ; c= - 0.0530

= $\frac{-b+\sqrt{b^2-4ac} }{2a}$ or $\frac{-b-\sqrt{b^2-4ac} }{2a}$

= $\frac{-(1)+\sqrt{(1)^2-4(78.2)(-0.0530)} }{2(78.2)}$ or $\frac{-(1)-\sqrt{(1)^2-4(78.2)(-0.0530)} }{2(78.2)}$

= 0.0204 or -0.0332

Going by the positive value; we have:

x = 0.0204

[A] = 0.0204

[B] = 0.0204

[C] = 0.0530 - x

= 0.0530 - 0.0204

= 0.0326

Total number of moles at equilibrium = 0.0204 + 0.0204 + 0.0326

= 0.0734

Finally, we can calculate the volume of the cylinder at equilibrium using the ideal gas; PV =nRT

if we make V the subject of the formula; we have:

$V = \frac{nRT}{P}$

where;

P (pressure) = 1 atm

n (number of moles) = 0.0734 mole

R (rate constant) = 0.0821 L-atm/mol-K

T = 273.15 K (fixed constant temperature )

V (volume) = ???

$V=\frac{(0.0734*0.0821*273.15)}{(1.00)}$

V = 1.64604

V ≅ 1.65 L

3 0

3 years ago

Why should scientists control most possible variables in their experiments?

irina [24]

Scientists should control most possible variables in experiments to get the most valid and correct data. If many variables are included in experiments it is more difficult to interpret what is causing a different outcome.

8 0

3 years ago

Investigate: Note the empty jars on the shelf that can be filled by using the slider. Set the amount to 2.000 moles of carbon (m

balandron [24]

Answer:

The molar mass of carbon

Explanation:

Before the mass (in grams) of two moles of carbon can be determined, the molar mass of the element would be needed.

This is because the number of mole of an element is the ratio of its mass and the molar mass. That is,

number of mole = mass/molar mass

Hence, the mass of elements can be obtained by making it the subject of the formular;

mass = number of mole x molar mass

Therefore, the molar mass of carbon would be needed before the mass of 2 moles of the element can be determined.

3 0

2 years ago