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jasenka [17]
3 years ago
12

Which of the following describes a perpetual-motion machine?

Chemistry
2 answers:
makkiz [27]3 years ago
5 0

Answer:

a motor that requires no energy input once it is running

Mashutka [201]3 years ago
4 0

Answer:

c

Explanation:

a p e x :)

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Answer: increasing the positive charge of the positively charged object and increasing the negative charge of the negatively charged object.

Explanation:

edge

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The material the start all reactions are ______ and the materials that are formed are called _____.
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What is the bond between Ca and Cl
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Help me please <br> Answer &amp; exp.
nordsb [41]

Explanation:

Some Rules Regarding Oxidation Numbers:

- Hydrogen has oxidation number of + 1 except in hydrides where it is -1

- Oxygen has oxidation number of -2 except in peroxides where it is -1

- Some elements have fixed oxidation numbers. E.g Halogen group elements has oxidation number of -1

- Oxidation number of a compound is the sum total of the individual elements and a neutral  compound has oxidation number of 0.

A. HI

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1 + x = 0

x = -1

B. PBr3

Br has oxidation number of - 1

Oxidation number of Pb:

x + 3 (-1) = 0

x = + 3

C. KH

Hydrogen has oxidation of + 1

Oxidation number of K:

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x = -1

D. H3PO4

Hydrogen has oxidation number of + 1

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3(1) + x + 4(-2) = 0

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8 0
3 years ago
Can anyone do this question.i really need a answer​
PilotLPTM [1.2K]

Answer:

17.4

Explanation:

kasi 15.2

16.2

=17.4 thanks me later pa brainliest din

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3 years ago
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