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3 years ago

One of the earliest atomic models was suggested by John Dalton in the early 1800s.

Chemistry

1 answer:

Nonamiya [84]3 years ago

7 0

Answer:

D. Atoms are like solid balls

Explanation:

John Dalton proposed that all matter is composed of very small things which he called atoms. This was not a completely new concept as the ancient Greeks (notably Democritus) had proposed that all matter is composed of small, indivisible (cannot be divided) objects. When Dalton proposed his model electrons and the nucleus were unknown.

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A buffer solution contains 0.11 mol of acetic acid and 0.13 mol of sodium acetate in 1.00 L. What is the pH of this buffer?

aleksley [76]

Answer:

Henderson Hasselbalch equation: pH = pKa + log [salt]/[acid]

You need to know the pKa for acetic acid. Looking it up one finds it to be 4.76

(a). pH = 4.76 + log [0.13]/[0.10]

= 4.76 + 0.11

= 4.87

(b) KOH + CH3COOH =>H2O + CH3COOK so (acid)goes down and (salt)goes up. Assuming no change in volume, you have 0.10 mol acid - 0.02 mol = 0.08 mol acid and 0.13 mol salt + 0.02 mol = 0.15 mol salt

pH = 4.76 + log [0.15]/[0.08]

= 4.76 + 0.27

= 5.03

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4 years ago

In photosynthesis what form of energy is sunlight converted to

Schach [20]

Photosinthisises equation is carbon dioxide + water ⇒ glucose (suger) + water
the light is needed to react with the CO² to create the oxygen needded

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4 years ago

A sample of helium gas has a volume of 620. Ml at a temp of 500 K. If we decrease the temperature to 100K while keeping the pres

Ne4ueva [31]

Answer:

A sample of helium gas has a volume of 620mL at a temperature of 500 K. If we ... to 100 K while keeping the pressure constant, what will the new volume be?

Explanation:

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3 years ago

Write a question about something else you would like to learn about extremophiles.

ivanzaharov [21]

I would probally say,

Can ants survive a plane ride?

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4 years ago

I just need help on the reactivity series stuff please I need to pass my grade check HELP

Setler [38]

Reactivity series:-

$\setlength{\unitlength}{0.8 cm}\begin{picture}(20,15)\thicklines\put(5,9.5){\large {\boxed{ \sf{Reactivity \: series}}}}\put(0.8,8){\large\sf K \qquad\qquad\qquad Potassium\qquad\qquad\qquad \: maximum}\put(0.8,7.2){\large\sf Na \qquad\qquad\qquad Sodium\qquad\qquad\qquad\quad \: reactivity}\put(0.8,6.2){\large\sf Ca\qquad\qquad\qquad \: Calcium}\put(0.8,5.2){\large\sf Mg\qquad\qquad\quad \: Magnesium}\put(0.8,4.2){\large\sf Al\qquad\qquad\qquad \: Aluminium\qquad\qquad\qquad \: decreasing}\put(0.8,3.2){\large\sf Zn\qquad\qquad\quad\qquad \: Zinc\qquad\qquad\qquad\qquad \:reactivity}\put(0.8,2.2){\large\sf Fe\qquad\qquad\quad\qquad Ferrous}\put(0.8,1.2){\large\sf Pb\qquad\qquad\qquad \: \:\: Lead}\put(0.8,0.2){\large\sf H\qquad\qquad\qquad \: \:Hydrogen}\put(0.8, - 0.6){\large\sf Cu\qquad\qquad\qquad \: Copper}\put(0.8, - 1.5){\large\sf Hg\qquad\qquad\qquad \: Mercury}\put(0.8, - 2.5){\large\sf Ag\qquad\qquad\qquad \: \:Silver}\put(0.8, - 3.5){\large\sf Au\qquad\qquad\qquad \: \: Gold\qquad\qquad\qquad\quad \: \: minimum reactivity}\put(9.3,8.2){\vector(0, - 2){12}}\end{picture}$

Ag is found as too less reactive so

Cu✓
Al✓
Ca✓

No element in universe can displace potassium (K) from its solution as it's most reactive .

Nota

Fe is also a reactive metal.

Only Cupper is less reactive than it

Al✓
Ca✓

Only Calcium can displace Mg

Mg and Ni can do ,Aurum(Gold) is least reactive so can't

Only Mg

Only Mg

Mg and Ni

Only Zn

#10

Zn and Pt

#11

Nota

As Ca is third most reactive metal

#12

Nota

4 0

3 years ago