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3 years ago

When does phenolphthalein turn pink?

Chemistry

2 answers:

Art [367]3 years ago

8 0

A) in the presence of a base

Gelneren [198K]3 years ago

7 0

Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions. Phenolphthalein is slightly soluble in water and usually is dissolved in alcohols for use in experiments.

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Nitric acid is produced commercially by the Ostwald process, represented by the following equations. 4 NH3(g) + 5 O2(g) 4 NO(g)

Marrrta [24]

Answer:

The answer to your question is: 1538095.2 kg of NH3

Explanation:

MW HNO3 = 63 kg

MW NO2 = 46 kg

3 NO2(g) + H2O(l)--- 2 HNO3(aq) + NO(g)

3(46) kg-------------- 2(63) kg

x --------------- 7600000 kg

x = 7600000 x 138/126 = 8323809.5 kg og NO2

MW NO = 30

2 NO(g) + O2(g)---2 NO2(g)

2(30) ------------------2(46)

x ---------------- 8323809.5 kg

x = 8323809.5 x 60/92 = 5428571.4 kg of NO

MW NH3 = 17 kg

4 NH3(g) + 5 O2(g) 4 NO(g) + 6 H2O(g)

4(17) -------------------- 4(30)

x ----------------------- 5428571.4

x = 5428571.4 x 34 / 120

x = 1538095.2 kg of NH3

4 0

3 years ago

How many moles are in 20g of potassium (K)?

otez555 [7]

Explanation:

Hi for this one u just need to remember and use the equation.

$moles = \frac{mass}{mr}$

then u find mr of potassium which is 39.1.

then u do

$\frac{20}{39.1}$

you get the answer as 0.5115 write ur answer to 3 significant figures which will be 0.512 moles .

hope this helps :)

7 0

3 years ago

What change causes a substance to change states of matter?

pochemuha

If the states of matter have changed such as from solid to liquid, you have to remove or add energy.

3 0

3 years ago

Read 2 more answers

Two common methods to generate an aldehyde is by oxidation of an alcohol and through ozonolysis.

kotykmax [81]

Answer:

a. True.

Explanation:

Only primary and secondary alcohols can oxidise to give an aldehyde. But a weak oxidizing agent must be used to prevent formation of a carboxylic acid or ketone.

weak oxidizing agents: Chromyl chloride, silver/oxygen/500°C