Answer:
d- Scientists have to follow government rules made to protect people.
Explanation:
Scientific research fosters our understanding of the world around us. It helps people to learn to promote critical thought and problem-solving. Although there may not be an immediate practical use of the research, in the long term the study could benefit humanity. Scientific research is the product of creative ideas and collaborative communication that the proper role of government is often restricted to funding the research. The role of the government is to perform its reasonable and valid duties of defending human rights and enhancing the independence of the human.
Answer:D
Explanation:
which of the following is not a rule when writing a hypothesis.
Will gift brainliest!
Is it testable
Is it a prediction
It must restate the question
It is a if/then statement
what is 98.723 meters= to blank cm
Answer:
9872.3 cm
Explanation:
If an atom has 16 protons, 14 neutrons, and 18 electrons. What is the charge of the nucleus?
. The atom has 2 more electrons than protons giving it a negative charge (2-)
you buy 30 g of soda that has a density of 50.0 g/mL. How many L did you buy?
Answer: 0.0006L
Explanation:
The density of a substance is given by the expression;
Density = Mass / Volume
Density = 50g/ml, Mass = 30g, Volume = ?
Making volume the subject of formular, we have; Volume = Mass / Density
∴ Volume = 30 g / 50g/ml = 0.6ml, then to Litre, we divide by 1000
The amount in Litres i bought is 0.0006L
Please answer both questions.
1. An ion formed from an atom has a 1- charge. The number of electrons present in the ion is 36 and the number of neutrons is 46. Identify the element.
options: chlorine, bromine, krypton, rhodium.
2. Identify which of the following particle(s) contain more electrons than neutrons.
I. 11H
II. 35 17Cl−
III. 23 11Na+
Answer:
1)Krypton
2)11H
Explanation:
electrons=protons
protons=atomic number
mass number=protons+neutrons
mass number is the superscript
atomic number is the subscript.
1)The answer is Krypton because its atomic number= number of protons=number of electrons is 36.
mass number is 46+36=82.
2)subscript=atomic number=number of protons=number of electrons
i. H = electrons=1
=neutrons=0
ii. Cl=electrons=17
=neutrons=35-17=18
iii. Na=electrons=11
=neutrons=23-11= 12
so the answer is Hydrogen because it has 1 electron and 0 neutron.
I hope this helps.
Rowena and helga are both performing an experiment with nickel metal. Rowena has a 5 gram sample and determines the density to be 8.9g/cm3. If helga has a nickel sample that is twice as large and has a mass of 10 grams what would be the density of helgas sample?
Answer:
The density of helgas sample is 17.8 g/cm³.
Explanation:
Given that,
Mass of sample of Rowena = 5 gram
Density = 8.9 g/cm³
Mass of sample of helga = 10 gram
We need to calculate the volume of sample
Using formula of volume
[tex]V=\dfrac{m}{\rho}[/tex]
Where, m = mass
[tex]\rho[/tex] = density
Put the value into the formula
[tex]V=\dfrac{5}{8.9}[/tex]
[tex]V=0.56\ cm^3[/tex]
We need to calculate the density of helgas sample
Using formula of density
[tex]\rho=\dfrac{m}{V}[/tex]
Where, m = mass
V = volume
Put the value into the formula
[tex]\rho=\dfrac{10}{0.56}[/tex]
[tex]\rho=17.8\ g/cm^3[/tex]
Hence, The density of helgas sample is 17.8 g/cm³.
10. Make your own unique problem for your classmates to solve for the
independent, dependent, and controlled variables. Make sure to include the
answers.
Answer:
Explanation:
Problem:
In a gender based experiment, the blood pressure of different ages of men is been checked and recorded to determine if there is any correlation. What will be the independent, dependent and controlled variables?
Answer:
A controlled variable is the variable that is left constant throughout the course of an experiment. The controlled variable here is the gender.
A dependent variable is the variable that is been determined or measured during the course of an experiment. The dependent variable here is the blood pressure.
An independent variable is the variable that is intentionally or decidedly altered during the course of an experiment. The independent variable here is the age.
A reaction between ammonia gas and chlorine gas produces
ammonium chloride and nitrogen gas. A reaction of 17.0 g of
ammonia with 26.6 g of chlorine gas gives off 3.5 g of nitrogen.
What mass of ammonium chloride is formed in the reaction?
g
Answer:
32.25
Explanation:
8NH3 + 3Cl2 → 6NH4Cl + N2
NH3 = 17 g/mol
number of moles = 1
NH4Cl= 43 g/mol
number of moles = 3/4
mass= 43 × ¾ ≈ 32.25 g
Answer:
40.1
Explanation:
its correct your welcome
Why is science important?
Answer:
science is valued by the society because the application of scientific knowledge helps to satisfy many basic human needs and improve living standards
Explanation:
Finding a cure for cancer and a clean form of energy are just two typical examples
Answer:
Science is about a whole lot more than that and to sum it up we believe that science is a way of helping the brain grow in finding new knowledge and helps us defeat our curiosity of how the world develops and works today. Science is important because it has helped form the world that we live in today.
Explanation:
In other words, science is one of the most important channels of knowledge. It has a specific role, as well as a variety of functions for the benefit of our society: creating new knowledge, improving education, and increasing the quality of our lives. Science must respond to societal needs and global challenges.
w h y d I d t h I s t a k e m e s o l o n g
Dog a is given one cup of food. Dog b is given 1/2 cup of food . Dog.c is given two cups of food at the end of the year dog c weighs the most. What is the the independent and dependent variable
Dependent variable: Weight
Independent variable: Amount of food
Explanation:
In experiments such as the one described, there are two or more factors involved, which act as variables. Additionally, these factors can be classified as dependent or independent. The difference between these two is that the independent factor is changed on purpose by the researcher. This occurs with the amount of food as each dog receives a different amount of food and this is controlled by the researcher.
On the other hand, the dependent variable is the main factor analyzed in the experiment or the factor that is modified by the independent variable. In the experiment presented, the dependent variable is weight because in this experiment the focus is to analyze how weight changes with different amounts of food, and this factor is affected by the independent variable.
what is (1.2 x 10^6 m) x ( 1.5 x 10^-7m) in scientific notation
Answer:
4.875 × 105
(scientific notation)
= 4.875e5
(scientific e notation)
= 487.5 × 103
(engineering notation)
(thousand; prefix kilo- (k))
Explanation:
This all the ways
A box has a length of 45 centimeters, a width of 7 centimeters, and a height of 15 centimeters. What is the volume? A sample of water has a mass of 14 grams and a volume of 2 cubic centimeters? What is the density of water
Answer:
Hey there!
The volume of the box would be 45(7)(15), or 4725 cm^3.
The density of any object is the mass divided by volume. Thus, the density of the water would be 14/2, or 7 g/cm^3.
Let me know if this helps :)
What is one way that potential energy might be involved in rescue team missions?
Answer:
You may be saving someone from a rock slide, where the rocks will fall at any time, before they fall they have potential energy.
The one way that potential energy might be involved in rescue team missions to save someone to fall is potential energy is used to hold one.
What is gravity?Gravity is the interaction that is because of the force of energy between the surface of the earth to the mass or any energy present on the earth's surface and the force becomes double with the weight.
The potential energy is a form of energy that is used against gravity to do the work which required energy and in rescue, the energy is needed in every coss to save one.
Therefore, one way that potential energy might be involved in rescue team missions to save someone to fall is because gravitational potential energy is used to hold one.
Learn more about gravity, here:
https://brainly.com/question/13810323
#SPJ2
If a piece of copper metal is placed in calcium chloride solution. What will you observe? Give reason for your answer.
Answer:
Explanation:
Reduction potential of Copper metal is .34 V and reduction potential of Calcium is - 2.87 V . So copper will not be able to reduce Calcium chloride to calcium . Hence no reaction will take place when a piece of copper metal is placed in calcium chloride solution .
what is the valence electron of Molybdenum
Answer:
[tex]\Large \boxed{\mathrm{1 \ valence \ electron}}[/tex]
Explanation:
Molybdenum is an element with an atomic number of 42.
An atom of Molybdenum has 42 electrons.
The electronic configuration of Molybdenum is 2, 8, 18, 13, 1.
The valence electrons are the number of electrons in the last shell.
Molybdenum has 1 valence electron.
If Lauren runs a 100 m race in 17.0 seconds, what is her time in minutes and how long does she run in kilometers?
Answer:
0.283 min.
0.1 km
Explanation:
Since there are 60 seconds in 1 minute, divide the time Lauren ran by 60.
17/60 = 0.283 min.
Since there are 1000 meters in 1 kilometer, divide the distance by 1000.
100/1000 = 0.1 km
hat type of mixture is chicken noodle soup?
A lab technician measures a sample of sulfur dichloride (SCl2) to contain 4.31 x 10^22 molecules of SCl2. How many atoms of chlorine are present in the sample?
Answer:
THE NUMBER OF ATOMS OF CHLORINE IN THE SAMPLE IS 25.95 * 10^45 ATOMS.
Explanation:
Number of molecules = 4.31 * 10^22 molecules of SCl2
From Avogadro's rule which states that equal volume of gases at the same temperature and pressure have the same number of molecules.
1 mole = 6.022 * 10 ^ 23 particles or atoms
So therefore, we equate the given value of SCl2 molecules and solve for the number of atoms of chlorine in the molecule
1 mole = 6.022 * 10^23 atoms
From the break down of SCl2
SCl2 -------> S+ + 2Cl -
So therefore, 2 moles of chlorine is present
2 moles = 2 * 6.022 *10^23
4.31 * 10^22 moles = x atoms
= 4.31 * 10 ^22 * 2 * 6.022 * 10^23 / 2
= 25.95482 * 10^45 atoms
In conclusion, the number of atoms of chlorine present in the sample is 25.95 * 10^45 atoms.
Which of these is a dependent variable in this demonstration?
A. the amount of water in the pan
B. the height of the water in the jar
C. the size of the bottle
D. the number of candles in the jar
Answer:
B). The height of the water in the jar.
Explanation:
A dependent variable is characterized as the variable that observes the change or effect caused by experimental manipulation in the independent variable. It is the variable that is being tested in the experiment. In the given experiment of the burning candle, 'the height of water in the jar' will rise or drop with manipulation in the independent variable i.e. 'the number of candles.' Since it is affected by the alteration in other variables, it is the dependent variable. Thus, option B is the correct answer.
At a birthday party in Phoenix, mom and dad begin inflating the balloons with helium. They both notice that the tank begins to cool down as they are inflating the balloon. Why?
Your question has been heard loud and clear.
Well , as the helium flows from tank to balloons , the helium inside the tank decreases , so air fills the remaining space inside the tank. Also , helium is stored under high pressure in the tank because , helium is lighter than air , so its molecules have high energy and this energy causes pressure which increases the temperature. Once the helium is let out , the tank cools down.
Thank you
how does the earth rotate?
Answer:
Earth's rotation is the rotation of Planet Earth around its own axis.
Explanation:
Earth rotates eastward, in prograde motion. As viewed from the north pole star Polaris, Earth turns counterclockwise.
Who would have first made this statement while observing cork under a microscope? "The cork looks like little rooms, or cells.”
Answer:
B. Schleiden
Explanation:
i just took the test
Answer:hooke
Explanation:me when your mom
The study of the universe and how it
evolved is called
Answer:
this is your answer hope it helps you
How long would it take in hours to administer exactly
500 mL of fluid through an IV with a drop factor of
30 gtt/mL. if the drip rate is 60 gttmin?
Answer:
4.167 hours
Explanation:
The drop factor is the amount of fluid falling for one millimeter of fluid in gttt/ml.
The flow rate is the volume administered for a specific period of time in ml/hr = volume / time
The unit of drip rate is gtt/min
The formula that shows the relationship is:
Drip rate = flow rate × drop factor
Given that:
Drip rate = 60 gtt / min, Flow rate = volume / time = 500 ml / t, drop factor = 30 gtt/ml
Drip rate = flow rate × drop factor
60 = 500 / t × 30
500 / t = 60/30
500 / t = 2
2t = 500
t = 500/2
t = 250 mins
1 hr = 60 min
t = 250 / 60 hours = 4.167 hours
How many significant figures are in 340500
Answer:
Five significant figures
Explanation:
You have to change the number to standard form
340500 = 3.405×10**5
** means raise to power
10**5
Where five represents the number of significant figures.
Answer:
4!
Explanation:
Maria wants to enter the science fair at her school. She has a list of ideas for her project. Which questions could be answered through scientific investigation? Check all that apply. Which marine biologist is the smartest? Does the rate of decay have an effect on the amount of gas produced? Is the information about photosynthesis difficult to understand? Which laboratory experiment is the most fun to perform? Which brand of stain remover is the best for getting out laundry stains?
Answer:
Does the rate of decay have an effect on the amount of gas produced?
Which brand of stain remover is the best for getting out laundry stains?
Explanation:
I just did it on Edge
Answer:
Does the rate of decay have an effect on the amount of gas produced?
Which brand of stain remover is the best for getting out laundry stains?
Explanation:
I just did the assignment
Thanks for the help :)
1. Describe what happens when two substances at different temperatures come into contact. Describe how the law of conservation of energy applies to this system.
2. Explain how the calorimeter works, and how you can calculate the heat given off or absorbed by the reaction being studied.
3. A calorimeter contains 500 g of water at 25°C. You place a hand warmer containing 100 g of liquid sodium acetate (NaAC) inside the calorimeter. When the sodium acetate finishes crystallizing, the temperature of the water inside the calorimeter is 32.2°C. The specific heat of water is 4.18 J/g-°C. What is the enthalpy of fusion (ΔHf) of the sodium acetate? Show your work.
Thanks!
1. When two substances at different temperatures come into contact, the substance that is at higher temperature will transfer energy, to the substance at a lower temperature such that their temperature become balanced.
By the law of conservation of energy the heat released by the substance initially at a higher temperature, is the same amount of heat gained by the substance originally at a lower temperature.
2. A calorimeter contains reactants and a substance to determine the heat absorbed, or the heat capacity of materials. This is done using the following equation, Q = mcΔT, where Q = 'heat absorbed / released.'
________________________________
3. We can calculate the energy released by the sodium acetate knowing that all the heat released is absorbed by the water (Part # 1).
[tex]\mathrm{Q =\:m * c * change\:in\:temperature} ,[/tex]
[tex]\mathrm{Q =\:500 * 4.18(specific\:heat\:of\:water) * \mathrm{32.2C -25C} } ,[/tex]
[tex]\mathrm{Q} = 500 * 4.18 * (32.3 - 25) = 15257 \mathrm{J} = 15.257 \mathrm{kJ}[/tex]
Now the enthalpy of fusion is expressed in kJ/mol, so we have to first calculate the moles of sodium acetate.
moles = mass / molar mass
Remember that the molar mass of sodium acetate is 82.0343 g/mol. Therefore the moles will be 100 / 82.0343 = 1.219 mol. Respectively the enthalpy should be 15.257/1.219 = 12.516 kJ/mol.
Which statement accurately describes the chemical symbol of an element?
Answer:
hello, i believe there's more information given on the question. could this be a multiple choice question? if yes please comment it below so i can further assist you.
Which Prosthetic groups are complex nonprotein molecules that participate in catalysis by providing functional groups that form a covalent intermediate between the enzyme and the substrate. Which of the following is an example of a coenzyme or cofactor that participates in a covalent catalysis reaction?
a. Pyridoxal phosphate
b. Sodium phosphate
c. Potassium chloride
d. None of the above
Answer:
A
Explanation:
Pyridoxal phosphate is your answer
What entropy change is associated with the reversible phase change from 1.0kg of ice to water at 0 ° C?
Answer:
1200 J/K
Explanation:
The formula for the entropy associated with a reversible phase change is
[tex]\Delta S= \dfrac{q_{\text{rev}}}{T}[/tex]
For a reversible phase change like melting,
[tex]q_{\text{rev}} = m\Delta_{\text{fus}}H[/tex]
Data:
Mass of ice = 1.0 kg
T = 0 °C
Calculations
1. Convert the mass of ice to grams
[tex]\text{Mass of ice} = \text{1.0 kg } \times \dfrac{\text{1000 g}}{\text{1 kg}} = \text{1000 g}[/tex]
2. Convert the temperature to kelvins
T = (0 + 273.15) K = 273.15 K
3. Calculate the heat needed to melt the ice
[tex]q_{\text{rev}} = m\Delta_{\text{fus}}H = \text{1000 g} \times \dfrac{\text{334 J}}{\text{1 g}} = \text{334 000 J}[/tex]
4. Calculate the entropy change
[tex]\Delta S = \dfrac{q_{\text{rev}}}{T} = \dfrac{\text{334 000 J}}{\text{273.15 K}} = \textbf{1200 J/K}[/tex]