All categories

3 years ago

As

Chemistry

2 answers:

FinnZ [79.3K]3 years ago

6 0

Answer:

A B D

Explanation:

<h2>PLS MARK AS BRAINLY</h2>

Mars2501 [29]3 years ago

4 0

Explanation:

area of rectangle=l×b

15=5×b
b=3cm

2.area of rectangle=l×b

28=l×4
l=7cm

3. perimeter of square=4×L

24=4×L
L=6cm

4. perimeter of rectangle=2(L+b)

14=2(4+b)
14=8+2b
2b=6
b=3cm

hope it helps.

You might be interested in

What charge would you expect for an formed by S?

sp2606 [1]

Answer:

in this the correct answer is option 2.

6 0

3 years ago

Is water an element compound or mixture

timama [110]

It is a Compound.

Water can't be a mixture because it is chemically bonded and cannot be separated into H2 and O by physical means.

And water cannot be an element, because it is made of atoms of different types [H and Oxygen]

4 0

3 years ago

The sea water has 8.0x10^-1 cg of element strontium. Assuming that all strontium could be recovered, how many grams of strontium

PilotLPTM [1.2K]

984 grams of strontium will be recovered from 9.84x10^8 cubic meter of seawater.

Explanation:

From the question data given is :

volume of strontium in sea water= 9.84x10^8 cubic meter

(1 cubic metre = 1000000 ml)

so 9 .84x10^8 cubic meter

$\frac{9 .84x10^8}{1000000}$ = 984 ml.

density of sea water = 1 gram/ml

from the formula mass of strontium can be calculated.

density = $\frac{mass}{volume}$

mass = density x volume

mass = 1 x 984

= 984 grams of strontium will be recovered.

98400 centigram of strontium will be recovered.

Strontium is an alkaline earth metal and is highly reactive.

4 0

3 years ago

Which group, metals or nonmetals, has the greatest chance to gain electrons and to become negative ions?

tatyana61 [14]

It would be non-metals

8 0

3 years ago

Hydrogen cyanide, HCN, is prepared from ammonia, air, and natural gas (CH₄), by the following process:

kykrilka [37]

Answer:

6.75 g of HCN can be produced by the reaction

Explanation:

Complete reaction is:

2NH₃ (g) + 3O₂ (g) + 2CH₄ (g) → 2HCN (g) + 6H₂O (g)

Let's determine the moles of each reactant:

11.5 g . 1mol / 17g = 0.676 moles of ammonia

12 g . 1 mol / 32g = 0.375 moles of oxygen

10.5 g . 1mol/ 16 g = 0.656 moles of methane

Now is all about rules of three:

2 moles of ammonia reacts with 3 moles of O₂ and 2 moles of methane

0.676 moles of NH₃ may react with:

(0.676 . 3) /2 = 1.014 moles of O₂

(0.676 . 2) / 2 = 0.676 moles of methane

Both can be the limiting reactant.

3 moles of O₂ react with 2 moles of NH₃ and 2 moles of methane

0.375 moles of O₂ will react with:

(0.375 .2) / 3 = 0.375 moles

The same amount for methane, 0.375 moles

2 moles of CH₄ reacts with 3 moles of O₂ and 2 moles of NH₃

0.656 moles of methane would react with 0.656 moles of NH₃

(0.656 . 3 ) /2 = 0.437 moles of O₂ I do not have enough O₂

Oxygen is the limiting reactant → We can work with the reaction now.

Ratio is 3:2. 3 moles of oxygen produce 2 moles of cyanide

0.375 moles of O₂ may produce (0.375 .2 ) / 3 = 0.250 moles

If we convert the moles to mass → 0.250 mol . 27 g / 1mol = 6.75 g

4 0

3 years ago