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Naddik [55]
3 years ago
14

15 points will mark brainliest

Chemistry
2 answers:
dybincka [34]3 years ago
6 0

Answer:

Option b as 100 years before also rain was not there is sahara dessert and now also it is not there..

Vladimir [108]3 years ago
4 0
You got it right, the answer is d
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how many calories is in one peanut if the volume of water is 10 mL and the water temperature is rise 4 degrees celsius
liraira [26]

Answer:

40.02 calories

Explanation:

V = 10 mL = 10g

we know t went <em>up</em> by 4°C, this is our ∆t as it is a change.

Formula that ties it together: Q = mc∆t

where,

Q = energy absorbed by water

m = mass of water

c = specific heat of water (constant)

∆t = temperature change

Q = (10 g) x (4.186 J/g•°C) x (4°C)

Q = 167.44 J

Joules to Calories:

167.44 J x 1 cal/4.184 J = 40.02 calories

(makes sense as in image it is close to the value).

4 0
3 years ago
I NEED HELP FAST!!!!! Can you tell me about examples of elements compounds and mixtures??? I have a DBA in a few minutes and I d
Jet001 [13]
Okay Elements can combine to created element compounds a few examples can be lets say Gold(Au) Is an example of an Iconic Compound (usually a common compound). An Element Mixture is literal a mixture Ex. Brass. Brass is usually 10% copper and 45% zinc. So in order to get Brass you must physically m<span />ix copper with zinc and the other metal (sorry i don't remember the name) Also mixtures tend to not be chemically constant, this is because it was physically mixed rather than all of the atoms be the same if they were chemically combined.
3 0
4 years ago
Write the Lewis structure for the product that forms when boron trifluoride combines with ammonia. Remember to show all non-zero
horrorfan [7]

Answer:

To draw or sketch a Lewis structure, formula or diagram, the chemical formula of the compound is essential. Without it you can not even know what are the atoms that make it up, in our case it is the one observed in the reaction shown:

BF_{3} + :NH_{3} ⇒ F3F_{3} BNH_{3}

In the structure obtained (see the Lewis structure in the drawing) the black dots correspond to the electrons of the non-shared pairs.  Because hydrogen has a single electron and a single orbital available to fill, it forms only a covalent bond represented by a long dash.   The same goes for boron and fluorine but in this case the fluorine has pairs of free electrons.

Explanation:

Lewis's structure is all that representation of covalent bonds within a molecule or an ion. In it, said bonds and electrons are represented by long dots or dashes, although most of the times the dots correspond to non-shared electrons and dashes to covalent bonds.

All existing compounds can be represented by Lewis structures, giving a first approximation of how the molecule or ions could be.

8 0
3 years ago
What is mass? How is the mass of an object<br> determined?
mina [271]
Mass is the inside of an obeject such as what it’s made up of
8 0
4 years ago
Solving fractions of
Ilya [14]

1) 1/2 of 24= 12

2) 1/3 of 24= 8

3) 1/4 of 24= 6

hope this helped

7 0
3 years ago
Read 2 more answers
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