How many protons, neutrons, and electrons does a magnesium atom with a mass number of 25 contain?

1. Most of the earth's surface is covered with

frozen [14]

Answer: water

Explanation:if you look at a globe most of it is blue and blue on a globe is water so that means water covers most of the earth

5 0

3 years ago

A gas system has an initial number of moles of 0.693 moles with the volume unknown. When the number of moles changes to 0.928 mo

lara [203]

Answer:

The initial volume in mL is 5959.2 mL

Explanation:

As the number of moles of a gas increases, the volume also increases. Hence, number of moles and volumes are directly proportional i.e

n ∝ V

Where n is the number of moles and V is the volume

Then, n = cV

c is the proportionality constant

∴n/V = c

Hence n₁/V₁ = n₂/V₂

Where n₁ is the initial number of moles

V₁ is the initial volume

n₂ is the final number of moles

and V₂ is the final volume.

From the question,

n₁ = 0.693 moles

V₁ = ?

n₂ = 0.928 moles

V₂ = 7.98 L

Putting the values into the equation

n₁/V₁ = n₂/V₂

0.693 / V₁ = 0.928 / 7.98

Cross multiply

∴ 0.928V₁ = 0.693 × 7.98

0.928V₁ = 5.53014

V₁ = 5.53014/0.928

V₁ = 5.9592 L

To convert to mL, multiply by 1000

∴ V₁ = 5.9592 × 1000 mL

V₁ = 5959.2 mL

Hence, the initial volume in mL is 5959.2 mL

5 0

3 years ago

Which of the following regions does NOT match its description?

Fantom [35]

The region that does not match its description is the fourth answer choice which is Abdominal region: spine

For the first answer choice - Cranial region: head

The cranial region encompasses the upper part of the head.

∴ The first answer choice matches its description.

For the second answer choice - Axillary region: armpits

The axillary region is an anatomical region under the shoulder joint where the arm connects to the shoulder. Therefore, it encompasses the armpits.

∴ The second answer choice matches its description.

For the third answer choice - Thoracic region: chest

The thoracic region runs from the base of the neck down to the abdomen. Therefore, it encompasses the chest

∴ The third answer choice matches its description

For the fourth answer choice - Abdominal region: spine

The abdominal region is divided into four quadrants which include are

1. Right upper quadrant fossa (RUQ)

2. Right lower quadrant fossa (RLQ)

3. Left lower quadrant fossa (LLQ)

4. Left upper quadrant fossa (LUQ)

It is also divided into nine (9) areas, all of which does not include the spine.

∴ The fourth answer choice does NOT match its description.

Hence, the region that does not match its description is the fourth answer choice which is Abdominal region: spine

Learn more here: brainly.com/question/11504303

8 0

2 years ago

What is the protons role in the atom?

Novosadov [1.4K]

The protons inside an atoms nucleus help bind the nucleus together. They also attract the negatively charged electons

7 0

3 years ago

Read 2 more answers

The Center for Disease Control publishes articles explaining the causes of seasonal West Nile virus. Research proves mosquitoes

Goshia [24]

Answer:

The correct answer is - Mosquitoes transmit the virus as parasites which feed on the blood of host organisms and inject the virus during feeding.

Explanation:

According to the CDC, the seasonal West Nile virus is caused by the mosquitoes of freshwater transmit this disease to humans and others. These mosquitoes are feed on the birds and pick these viruses.

These viruses stick on mosquitoes and when they feed on the blood of humans they transmit these viruses by injecting viruses into the blood of humans.

4 0

3 years ago