Which of the following most likely happens when thermal energy is removed from a chemical reaction?

Must show units and how they cancelli 1.) 175 km to um 3.) 385 nm to dm 5.) 492 um tom 7.) 52 x 103 dm to mm 9.) 321x 1035 mm to

morpeh [17]

Explanation:

1.) 175 km to μm

$1 km=10^9 \mu m$

$175 km=175\times 10^9\mu m=1.75\times 10^{11} \mu m$

3.) 385 nm to dm

$1 nm=10^{-8} dm$

$385 nm=385\times 10^{-8} dm=3.85\times 10^{-6} dm$

5.) 492 μm to m

1 μm = $10^{-6} m$

$492 \μm=492\times 10^{-6} m=4.92\times 10^{-4} m$

7.) $52\times 10^3$ dm to mm

1 dm = 100 mm

$52\times 10^3 dm=52\times 10^3\times 100 mm=5.2\times 10^{6}dm$

9.) $321\times 10^{35}$ mm to km

$1 mm = 10^{-6} km$

$321\times 10^{35} mm=321\times 10^{35}\times 10^{-6} km=3.21\times 10^{31} km$

11.) $456\times 10^3$ m to km

m = 0.001 km

$456\times 10^3m =456\times 10^3 m\times 0.001 km=456 km$

13.) $422\times 10^3$ m to nm

$1 m = 10^{9} nm$

$422\times 10^3 m=422\times 10^3\times 10^{9} nm=4.22\times 10^{14} nm$

15.) $4.87\times 10^{30}$ m to pm

$1 m = 10^{12} pm$

$4.87\times 10^{30} m=4.87\times 10^{30}\times 10^{12} pm=4.82\times 10^{42} pm$

17.) $5.26\times 10^3$ m to um

1 m = $10^{6} \mu m$

$5.26\times 10^3 m=5.26\times 10^3\times 10^6 \mu m=5.26\times 10^{9} \mu m$

19.) $1.25\times 10^{35}$ m to Mm

1 m = $10^{-6} Mm$

$1.25\times 10^{35} m=1.25\times 10^{35}\times 10^{-6} Mm=1.25\times 10^{-29} Mm$

21.) $4.22\times 10^3$ Tm to nm

$1 Tm = 10^{21} nm$

$4.22\times 10^3 Tm=4.22\times 10^3\times 10^{21} nm=4.22\times 10^{24} nm$

6 0

3 years ago

A chemist determined by measurements that 0.050 moles of aluminum participated in a chemical reaction. Calculate the mass of alu

Law Incorporation [45]

Answer:

13.5 g

Explanation:

This question is solved easily if we remember that the number of moles is obtained by dividing the mass into the atomic weight or molar mass depending if we are referring to elements or molecules.

Therefore, the mass of aluminum in the reaction will the 0.050 mol Al times the atomic weight of aluminum.

number of moles = n = mass of Al / Atomic Weight Al

⇒ mass Al = n x Atomic Weight Al = 0.050 mol x 27 g mol⁻¹

= 13.5 g

We have three significant figures in 0.050 and therefore we should have three significant figures in our answer.

8 0

3 years ago

I NEED HELP PLEASEEEEEE I WILL RATE BRAINLIEST!!!!

MrRa [10]

0.002 moles is the answer

8 0

3 years ago

Please help ASAP!! I am not sure how to solve this!

umka2103 [35]

Answer:

Potassium (K) has 19 protons.

Each neutral atom of Potassium has 19 electrons.

Explanation:

A) Potassium has 19 protons because the atomic number tells us how many protons are in an atom of the element. (The atomic number is the number above the element symbol. For example, the number above "K" is 19, which is the atomic number).

B) If an atom is neutral, this means that the atom has neutral energy. Protons give positive energy and electrons give negative energy. For the atom to be neutral, the atom must have balanced energy, therefore, making the number of electrons equal to the number of protons in a neutral atom.

7 0

3 years ago

When the reactive alkali metal sodium is reacted with poisonous chlorine gas, sodium chloride or table salt is produced. Is mass

PIT_PIT [208]

Answer:

Yes, Mass is conserved.

Explanation:

Every chemical reactions obey the law of conservation of mass. The law of conservation of mass states that in chemical reactions, mass is always constant.

Equation:

2Na + Cl₂ → 2NaCl

From the equation above, one can observe that the reaction started using 2 atoms of Na and it produced 2 atoms of the same element in NaCl. A molecule of Cl produced 2 atoms of Cl in the NaCl

Design a simple experiment to support your answer:

Aim: To demonstrate the law of conservation of mass

One Na atom weighs 23g

Two Na atom will weigh 2 x 23 = 46g

1 atom of Cl is 35.5g

1 molecule of Cl containing two atoms of Cl will weigh 2 x 35.5 = 71g

Total mass of reactants = mass of 2Na + 1Cl₂ = (46 + 71)g = 117g

On the product side, Mass of 1 NaCl = 23+ 35.5 = 58.5g

Two moles of NaCl will give 2 x 58.5g = 117g

Since the mass on both side is the same, one can say mass is conserved.

7 0

3 years ago