1. SEP Develop Models Develop a model to show the chemical potential energy of

How would you characterize a liquid?

Naya [18.7K]

Answer:

The correct answer is D!

Explanation:

Liquids have a fixed shape and fixed volume. Liquids take the shape of their containers. Hope you have a great dayy!

6 0

3 years ago

True or false? An organism may play more than one role in a food web

almond37 [142]

FALSE

Organisms may play only one role in an ecosystem. ... Each of the organisms in an ecosystem fills the energy role of producer, consumer, or decomposer.

~~~~iln~~~~~~

3 0

3 years ago

Read 2 more answers

In a certain city, electricity costs $0.17 per kW·h. What is the annual cost for electricity to power a lamp-post for 5.50 hours

Anon25 [30]

Answer:

(a) = $34.123

(b) = $8.532

(c) Additional cost of fluorescent bulb is justified

Explanation:

Cost of electricity = $0.17 per kW·h

(a) For a 100 watt bulb which is the same as 100/1000 or 0.1 kW, the cost per hour =

0.1 × 0.17 = $0.017/h

and for 5.5 hours = 0.017×5.5 = $0.0935

The annual cost, which is 365 days, we have

Annual cost = $0.0935 × 365 = $34.123

(b) For the energy efficient 25-watt bulb, we have

25/1000 = 0.025kW

Power cost per annum =

0.025kW×$0.17 per kW·h×5.5×365 = $8.532

(c) Total cost of incandescent bulb = $0.89 total cost of using the incandescent bulb is $34.123 + $0.89 = $35.02

Total cost of using the energy efficient fluorescent bulb is about $3.49

Total cost of using the energy efficient bulb = $8.532 + $3.49 = $12.02

Total cost of incandescent bulb = $35.02 while total cost of energy efficient bulb is = $12.02

$12.02 <$35.02

Additional cost of fluorescent bulb is justified

8 0

3 years ago

What is the pH of a mixture of 0.042 M NaH2PO4 and 0.058 M Na2HPO4? Hint: The pKa of phosphate is 6.86.

AlekseyPX

Answer:

The pH value of the mixture will be 7.00

Explanation:

Mono and disodium hydrogen phosphate mixture act as a buffer to maintain pH value around 7. Henderson–Hasselbalch equation is used to determine the pH value of a buffer mixture, which is mathematically expressed as,

$pH=pK_{a} + log(\frac{[Base]}{[Acid]})$

According to the given conditions, the equation will become as follow

$pH=pK_{a} + log(\frac{[Na_{2}HPO_{4} ]}{[NaH_{2}PO_{4}]})$

The base and acid are assigned by observing the pKa values of both the compounds; smaller value means more acidic. NaH₂PO₄ has a pKa value of 6.86, while Na₂HPO₄ has a pKa value of 12.32 (not given, but it's a constant). Another more easy way is to the count the acidic hydrogen in the molecular formula; the compound with more acidic hydrogens will be assigned acidic and vice versa.

Placing all the given data we obtain,

$pH=6.86 + log(\frac{0.058}{0.042})$

$pH=7.00$

5 0

3 years ago

When multiplying numbers in scientific notation what do you do with exponents?

Basile [38]

Answer:

Subtract them.

Explanation:

''''"Since all number in scientific notation have base 10, we can always multiply them and divide them. To multiply two numbers in scientific notation, multiply their coefficients and add their exponents. To divide two numbers in scientific notation, divide their coefficients and subtract their exponents."""""

I was actually learned about this in school just found an source.

6 0

4 years ago