1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
natima [27]
3 years ago
13

How many milliliters of water at 25.0°C with a density of 0.997 g/mL must be mixed with 163 mL of coffee at 97.9°C so that the r

esulting combination will have a temperature of 54.0°C? Assume that coffee and water have the same density and the same specific heat (4.18 J/g·°C) across the temperature range.
Chemistry
1 answer:
Stolb23 [73]3 years ago
8 0

Answer:

248 mL

Explanation:

According to the law of conservation of energy, the sum of the heat absorbed by water (Qw) and the heat released by the coffee (Qc) is zero.

Qw + Qc = 0

Qw = -Qc [1]

We can calculate each heat using the following expression.

Q = c × m × ΔT

where,

  • c: specific heat
  • m: mass
  • ΔT: change in the temperature

163 mL of coffee with a density of 0.997 g/mL have a mass of:

163 mL × 0.997 g/mL = 163 g

From [1]

Qw = -Qc

cw × mw × ΔTw = -cc × mc × ΔTc

mw × ΔTw = -mc × ΔTc

mw × (54.0°C-25.0°C) = -163 g × (54.0°C-97.9°C)

mw × 29.0°C = 163 g × 43.9°C

mw = 247 g

The volume corresponding to 247 g of water is:

247 g × (1 mL/0.997 g) = 248 mL

You might be interested in
100 points right here first come first serve. amos thejonah2016
Kisachek [45]

Answer:

siya at ako ayieeeeeeeeee

7 0
2 years ago
Which determines the chemical properties of minerals?
azamat
The chemical makeup found on the periodic table.
5 0
3 years ago
URGENT!!!
Ksenya-84 [330]

Answer: The balance of the reaction shifts toward the endothermic reaction.

Explanation:

An ENDOTHERMIC REACTION requires input of HEAT ENERGY to drive it FORWARD from reactants, unto completion of products.

So, on increasing the temperature (available heat) the REVERSIBLE REACTION favors the shifts towards the endothermic reaction

8 0
3 years ago
What is the half-life of a pharmaceutical if the initial dose is 500 mg and only 31 mg remains after 6 hours?
Sergeu [11.5K]

Answer:

\large \boxed{\text{b. 1.5 h}}

Explanation:

1. Calculate the rate constant

The integrated rate law for first order decay is

\ln \left (\dfrac{A_{0}}{A_{t}}\right ) = kt

where

A₀ and A_t are the amounts at t = 0 and t

k is the rate constant

\begin{array}{rcl}\ln \left (\dfrac{500}{31}\right) & = & k \times 6\\\\\ln 16.1 & = & 6k\\2.78& =& 6k\\k & = & \dfrac{2.78}{6}\\\\& = & 0.463 \text{ h}^{-1}\\\end{array}

2. Calculate the half-life

t_{\frac{1}{2}} = \dfrac{\ln2}{k} = \dfrac{\ln2}{\text{0.463  h}^{-1}} = \textbf{1.5 h}\\\\ \text{The half-life is $\large \boxed{\textbf{1.5 h}}$}

4 0
3 years ago
Some organisms that are alive today do not look exactly like organisms that lived in the past. However, if a comparison of DNA s
ololo11 [35]

Fossils are the preserved remains or traces of animals, plants, and other organisms from the past.

Fossils are important evidence for evolution because they show that life on earth was once different from life found on earth today.

Usually only a portion of an organism is preserved as a fossil, such as body fossils (bones and exoskeletons ), trace fossils (feces and footprints), and chemofossils (biochemical signals).

Paleontologists can determine the age of fossils using methods like radiometric dating and categorize them to determine the evolutionary relationships between organisms.

5 0
3 years ago
Read 2 more answers
Other questions:
  • Poor thermal conductors. Poor electrical conductors. Brittle solids - not malleable or ductile. Little or no metallic luster. Ga
    6·1 answer
  • How many moles of electrons are transferred in the folllowing balanced chemical equation 4fe + 3o2?
    14·1 answer
  • 16. What mass of sulfur has to burn to produce 4.5L SO2 at 300°C and 101 kPa in the following reaction? A. 41.0 g S B. 3.07 g S
    14·1 answer
  • What is the name of group 5a
    15·1 answer
  • G Calculate the mass, in grams, of 225.0 atoms of cadmium, Cd (1 mol of Cd has a mass of 112.41 g).
    7·1 answer
  • Please select the word from the list that best fits the definition Composed of one type of compound molecule compound mixture ch
    10·1 answer
  • Whats is tge electron configuration of Ag2+ please answer asap..
    11·1 answer
  • starting with methane ,name all the steps and write the equations involved in tetrachlorination.Remember all arrows sharing move
    8·1 answer
  • PLS HELP!
    6·1 answer
  • MHA FANS FINISH THE MEME<br> who's that Pokémon?<br><br> Fudge!<br> -bakugou
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!