Ask question

Ask question

All categories

Angelina_Jolie [31]

2 years ago

15

A student places 6.00 cups of water in a beaker. Two cups of water have the weight of 1.00 pounds. How much heat is needed to ra

ise the temperature of the water from 17.3°C to a boil? *
A) 15.9 J
B) 4.71 x 10⁵J
C) 470,849.28J
D) 9.42 x 10⁵ J

1 answer:

vivado [14]2 years ago

8 0

A

Explanation:

The awnser is a

You might be interested in

How does insulin bind to cells and the mechanism involved in triggering the cells to take in glucose

Lera25 [3.4K]

Explanation:

Once blood glucose levels increase, pancreatic insulin migrates into a fat cell via the blood stream. Insulin then binds in the plasma membrane of the cell to an Insulin Receptor (IR). Through autophosphorylation, phosphate groups are then added to the IR, causing GLUT4 molecules to come to the cell's surface.

7 0

2 years ago

Consider 100.0 g samples of two different compounds consisting only of carbon and oxygen. One compound contains 27.2 g of carbon

Pani-rosa [81]

<u>Answer:</u> The ratio of carbon in both the compounds is 1 : 2

<u>Explanation:</u>

Law of multiple proportions states that when two elements combine to form two or more compounds in more than one proportion. The mass of one element that combine with a given mass of the other element are present in the ratios of small whole number. For Example: $Cu_2O\text{ and }CuO$

<u>For Sample 1:</u>

Total mass of sample = 100 g

Mass of carbon = 27.2 g

Mass of oxygen = (100 - 27.7) = 72.8 g

To formulate the formula of the compound, we need to follow some steps:

<u>Step 1:</u> Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{27.2g}{12g/mole}=2.26moles$

Moles of Oxygen = $\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{72.8g}{16g/mole}=4.55moles$

<u>Step 2:</u> Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 2.26 moles.

For Carbon = $\frac{2.26}{2.26}=1$

For Oxygen = $\frac{4.55}{2.26}=2.01\approx 2$

<u>Step 3:</u> Taking the mole ratio as their subscripts.

The ratio of C : O = 1 : 2

Hence, the formula for sample 1 is $CO_2$

<u>For Sample 2:</u>

Total mass of sample = 100 g

Mass of carbon = 42.9 g

Mass of oxygen = (100 - 42.9) = 57.1 g

To formulate the formula of the compound, we need to follow some steps:

<u>Step 1:</u> Converting the given masses into moles.

Moles of Carbon = $\frac{\text{Given mass of Carbon}}{\text{Molar mass of Carbon}}=\frac{42.9g}{12g/mole}=3.57moles$

Moles of Oxygen = $\frac{\text{Given mass of oxygen}}{\text{Molar mass of oxygen}}=\frac{57.1g}{16g/mole}=3.57moles$

<u>Step 2:</u> Calculating the mole ratio of the given elements.

For the mole ratio, we divide each value of the moles by the smallest number of moles calculated which is 3.57 moles.

For Carbon = $\frac{3.57}{3.57}=1$

For Oxygen = $\frac{3.57}{3.57}=1$

<u>Step 3:</u> Taking the mole ratio as their subscripts.

The ratio of C : O = 1 : 1

Hence, the formula for sample 1 is $CO$

In the given samples, we need to fix the ratio of oxygen atoms.

So, in sample one, the atom ratio of oxygen and carbon is 2 : 1.

Thus, for 1 atom of oxygen, the atoms of carbon required will be = $\frac{1}{2}\times 1=\frac{1}{2}$

Now, taking the ratio of carbon atoms in both the samples, we get:

$C_1:C_2=\frac{1}{2}:1=1:2$

Hence, the ratio of carbon in both the compounds is 1 : 2

8 0

2 years ago

What is the National Suicide rate for Teens?

Butoxors [25]

I think it is 11% I read it on a article on msn.

4 0

2 years ago

Hibernation is _______. A. An example of an abiotic cycle b. Triggered by changes in the weather c. Caused only by biotic factor

natta225 [31]

The correct answer is option b, that is, triggered by changes in the weather.

Hibernation refers to a state of lower metabolism and inactivity usually witnessed in endotherms. This condition is featured by a slow heart rate, slow breathing, low metabolic rate, and low body temperature. It assists the majority of the endotherms to thrive in the cold seasons. For example, hibernation of a bear in winters. Therefore, weather change can stimulate hibernation.

6 0

2 years ago

How many moles are in 25 g KMnO4

Ronch [10]

Answer:

0.158 moles KMnO4

Explanation:

According to the Periodic Table,

K = 39.10 g/mol

Mn = 54.94 g/mol

O = 16.00 g/mol

KMnO4 = 39.10 g/mol + 54.94 g/mol + 4(16.00 g/mol) = 158.04 g/mol

25.0 grams KMnO4 1 mole

----------------------------- x -------------------------- = 0.158 moles KMnO4

158.04 grams

8 0

2 years ago