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PtichkaEL [24]
3 years ago
10

Why were gold and copper the first forms of matter investigated by humans

Chemistry
1 answer:
baherus [9]3 years ago
8 0
They were valuable to the eyes of man then.
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In an alkane the mass ratio between hydrogen and carbon is 7/36. What is the formula of alkane?
ch4aika [34]

Answer:

CnH2n+2 formula

Explanation:

Alkanes have the general formula CnH2n+2, so if an alkane had 7 carbon atoms, it would have the molecular formula C7H16.

3 0
1 year ago
A chemical engineer determines the mass percent of iron in an ore sample by converting the Fe to Fe²⁺ in acid and then titrating
neonofarm [45]

The mass percent of iron in the ore is 31.6%

<h3>Steps</h3>

8H⁺(aq) + 5Fe²⁺(aq) + MnO⁻₄(aq) → 5Fe³⁺(aq) + Mn²⁺(aq) + 4H₂O(l)

V(MnO4^-)=39,32 mL

c(MnO4^-)=0,0319M

n(MnO4^-)=c*V=1,254308 mmol

n(Fe^{2+})=5*n(MnO4^-)=6,27 mmol

Equation

Fe+2H->Fe^+2 + H2

n(Fe)=n(Fe^{2+} )=6,27 mmol

m(Fe)=n*Ar=350,27mg=0,35027g

mass percent(Fe in ore)=m(Fe)/m(ore)*100

=31,61 percent

The mass percent of iron in the ore is 31.6%

<h3>What is the equation for the balance formula?</h3>

An equation for a chemical reaction is said to be balanced if both the reactants and the products have the same number of atoms and total charge for each component of the reaction. In other words, both sides of the reaction have an equal balance of mass and charge.

<h3>An illustration of a balanced equation</h3>

For instance, consider about the reaction: O2 (g) + 2Mg(s) = 2MgO (g) Two magnesium and two oxygen atoms are present in this reaction on both the reactant and product sides.

learn more about balanced equation here

brainly.com/question/26694427

#SPJ4

8 0
1 year ago
How do you know that volume of a diamond is 15.1g
marshall27 [118]

Answer:

Density = mass / volume,  

        therefore volume = mass / density. Note that 1 mL = 1 cubic centimeter.

Explanation:

Volume = 15.1g / 3.52g/mL = 4.3mL = 4.3 cubic centimeters.

then a  diamond has a density of 3.52 g/mL.

4 0
3 years ago
On a graph , which type of line shows a direct proportion?
svetoff [14.1K]
C - straight line
.....................................................................................
5 0
3 years ago
Read 2 more answers
Which statement describes a difference between the humid continental and subarctic climates?
-BARSIC- [3]

Answer:

The humid continental climate has hot summers, while the subarctic climate has short, cool summers.

Explanation:

I did the lesson already and got it correct lol

6 0
3 years ago
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