All categories

3 years ago

Which of these is an element? A. carbon B. carbon dioxide C. air D. water

Chemistry

2 answers:

Sloan [31]3 years ago

8 0

I think it's B carbon dioxide

Kaylis [27]3 years ago

4 0

Elements are pure substances. Carbon is the only one that is pure.

You might be interested in

Matter of the universe is made of building blocks known as atoms TrueFalse

zaharov [31]

True. The building blocks of life are atoms

7 0

3 years ago

What is a number bond.

GenaCL600 [577]

Explanation:

number bonds are pairs of numbers that can be added together to make another number e.g. 4 + 6 = 10. They are some of the most basic and most importantparts ofmaths for children to learn

3 0

2 years ago

Calculate the ph of a solution containing 0.0451 m potassium hydrogen tartrate and 0.028 m dipotassium tartrate. The ka values f

Marina86 [1]

Given buffer:

potassium hydrogen tartrate/dipotassium tartrate (KHC4H4O6/K2C4H4O6 )

[KHC4H4O6] = 0.0451 M

[K2C4H4O6] = 0.028 M

Ka1 = 9.2 *10^-4

Ka2 = 4.31*10^-5

Based on Henderson-Hasselbalch equation;

pH = pKa + log [conjugate base]/[acid]

where pka = -logKa

In this case we will use the ka corresponding to the deprotonation of the second proton i.e. ka2

pH = -log Ka2 + log [K2C4H4O6]/[KHC4H4O6]

= -log (4.31*10^-5) + log [0.0451]/[0.028]

pH = 4.15

4 0

2 years ago

3.5 grams is equivalent to how many kilograms? 3500 kg 35,000 kg 0.35 kg 0.0035 kg

bagirrra123 [75]

There are 1000 grams in a kg.
To convert g to kg, dovide by 1000.

3.5/1000= 0.0035 kg

Final answer: D

4 0

3 years ago

Which formula can be used to find velocity if kinetic energy and mass are known?

astraxan [27]

Answer:

$v = \sqrt{ \frac{2ke}{m} }$

option D is the correct option.

Here,

If an object of mass 'm' moving with a velocity'v' then,

$kinetic \: energy = \frac{1}{2} m {v}^{2} \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: {v}^{2} = \frac{2ke}{m} \\ \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: {v}^{2} = \sqrt{ \frac{2ke}{m} }$

hope this helps...

Good luck on your assignment..

5 0

2 years ago