In a scientific experiment, the factor that may change in response to the manipulated variable is called the ______ variable.

1) Answer is: False.

A period in the periodic table is a horizontal row. For example, sodium and chlorine are in third period and they have very different properties. Sodium is solid metal and chlorine is gaseous nonmetal. Elements in the same row have the same number of electron shells, but different proporties.

2) Answer is: True.

Group is a column of elements in the periodic table. For example, lithium and sodium are in 1 group of the periodic table and they both have one valence electron.

3) Answer is: valence electrons.

For example, electron configuration of oxygen atom: ₈O 1s² 2s² 2p⁴.

Oxygen atom has six valence electrons, so it is in 16 group of Periodic table of elements.

Answer:

I think it is da C

Explanation:

Later ✌️

The energy of the X-ray photons with a wavelength of [tex]\(0.135 \, \text{nm}\)[/tex] is [tex]\(1.473 \times 10^{-18} \, \text{kJ}\)[/tex].

To calculate the energy of X-ray photons with a given wavelength, you can use the energy-wavelength relationship given by Planck's equation:

[tex]\[ E = \dfrac{hc}{\lambda} \][/tex]

Where:

Let's plug in the values:

[tex]\[ E = \dfrac{(6.626 \times 10^{-34} \, \text{J} \cdot \text{s}) \times (3.00 \times 10^8 \, \text{m/s})}{0.135 \times 10^{-9} \, \text{m}} \][/tex]

[tex]\[ E \approx \dfrac{(1.9878 \times 10^{-25} \, \text{J} \cdot \text{m})}{0.135 \times 10^{-9} \, \text{m}} \][/tex]

[tex]\[ E \approx 1.473 \times 10^{-15} \, \text{J} \][/tex]

Now, convert this energy from joules to kilojoules:

[tex]\[ E_{\text{kJ}} = \dfrac{1.473 \times 10^{-15} \, \text{J}}{1000} \][/tex]

[tex]\[ E_{\text{kJ}} \approx 1.473 \times 10^{-18} \, \text{kJ} \][/tex]

So, the energy of the X-ray photons with a wavelength of [tex]\(0.135 \, \text{nm}\)[/tex] is approximately [tex]\(1.473 \times 10^{-18} \, \text{kJ}\)[/tex].

The complete question: X-ray photons with a wavelength of 0.135 nm . express the energy numerically in kilojoules per mole.

Final answer:

Magnetism is not an intensive physical property, while boiling point, thermal conductivity, and volume are examples of intensive physical properties.

Explanation:

An intensive physical property is a property that does not depend on the amount of the substance and physical state at a given temperature and pressure. Out of the given options, magnetism is not an intensive physical property because it depends on the presence of a magnetic field and can vary depending on the strength of the field. On the other hand, boiling point, thermal conductivity, and volume are all examples of intensive physical properties as they do not depend on the amount of the substance.

Usually the uncertainty of a graduated cylinder is given however if it is not, then it is simply assumed to be equal to half of the least interval of that instrument. In this case, the least interval is 10 ml, so half of this is 5 ml. Hence, the graduated cylinder has an uncertainty of +/- 5 ml

Answer:

It is A) A and wave B. The human ear would hear.

Explanation:

It is on Usa Test Prep and Wave A has a greater amplitude than wave B. That is perceived as a louder sound. Wave B has a higher frequency; that would be perceived as a higher pitch.

Answer:

to increase surface area or A

Explanation:

Final answer:

Gases are not a part of every chemical reaction, unlike reactants, products, and energy changes which are essential components of all reactions.

Explanation:

What is not part of every chemical reaction? The answer is C. gases. While every chemical reaction involves reactants and products, and energy changes (either absorption or release), not all chemical reactions produce or involve gases. Reactants are the substances present at the beginning of a reaction, and products are the substances formed as a result of the reaction. Energy is a fundamental component of chemical reactions, as it is either released or absorbed during the process. In contrast, the production of gases is specific to certain types of reactions and is not a universal aspect of all chemical reactions.

In every chemical reaction, energy is not always a part of the reactants or products involved. While reactants and products are essential components of a chemical reaction, gases and energy are not universally present in every reaction.

Final answer:

The wind blowing a sand dune exemplifies sediment deposition by wind, commonly observed in deserts and coastal areas, and involves processes that create well-sorted, often red colored sands. This phenomenon is also significant in planetary science, evidenced by features on Mars reshaped by wind, such as large dune fields and yardangs aligned with the wind direction.

Explanation:

The wind blowing a sand dune is an example of sediment deposited by wind, which is a process often observed in deserts and coastal regions. Sand dunes formed by wind deposition are typically composed of well-sorted sand, which can be red in color due to the oxidation of iron-bearing minerals. This type of sediment transport is due to the variable energy of the wind, which can range from gentle breezes capable of slowly shifting grains of sand to powerful gusts that rapidly reconfigure the dune landscape.

Studying the effects of wind on sand dunes is not only relevant to Earth but also to planetary science, as seen with the exploration of surface features on Mars. Here, wind plays a pivotal role in reshaping the landscape, creating features such as large dune fields, intricate patterns caused by dust devils, and exposing underlying darker materials that give rise to contrast in coloration on the Martian surface. The dynamic nature of wind erosion and deposition is evident in the existence of yardangs, ridges that are aligned with the dominant wind direction and carved by persistent, strong winds.

In summary, the movement of a sand dune by wind is a clear illustration of the power of natural forces to shape and alter landscapes on Earth and other celestial bodies like Mars, particularly in areas characterized by a scarcity of water and vegetation that might otherwise anchor the surface material.

Answer:  114.29 mL

Explanation:

We are given that density of ether = 0.70 g/ml

Mass of ether= 80.0 g

Formula to calculate the density is given by :-

[tex]\text{Density}=\dfrac{\text{Mass}}{\text{Volume}}[/tex]

Substitute the value of density and mass , we get

[tex]0.70=\dfrac{80.0}{\text{Volume}}\\\\\Rightarrow\text{Volume}=\dfrac{80}{0.70}=114.285714286\approx114.29\ mL[/tex]  [Rounded to the nearest two decimal places.]

Hence, the volume of ether = 114.29 mL

I believe that in this case the controlled parameter is the type of animal that they are observing. There are a lot of animals in the ocean, therefore to have a scope of their study of observation, they are controlling or limiting their observations on the whale alone. Hence the controlled parameter is the type of animals, whales.

Answer:

The answer is B. Place a 2 in front of the HCl

Ba + 2HCl → BaCl2 + H2

Explanation:

According to the law of the conservation of matter, no atom can create or destroy in a chemical reaction. Then the number of atoms that are present in the reagents has to be equal to the number of atoms present in the products. Therefore, if the number of atoms is not equal, the equation must be balanced.

First you must determine the amount of atoms of each element present in both reagents and products. For that you must observe the subscripts next to each atom. In this case:

Reagents (left side of the reaction):

Products (right side of the equation):

You can see that there aren't the same number of atoms of Cl and H in reagents and products. So you have to balance the chemical reaction.

In a chemical equation, you can change coefficients, but you should never alter the subscripts. And it is always preferable not to start balancing with H. In this case, you start balancing the chlorine. For that you add the coefficient 2 to the HCl molecule to the right of the equation to balance it with the 2 Cl atoms to the left of the equation (present in BaCl2). So:

Ba + 2HCl → BaCl2 + H2

Now you must determine the amount of atoms of each element present in both reagents and products again to see if the reaction is balanced or not. Remember that by multiplying the coefficient by the subindice of each atom, you get the amount of that atom.

Reagents (left side of the reaction):

Products (right side of the equation):

You can see that you have the same amount of each atom on each side of the reaction. This means that the reaction is balanced.

So the answer is

Ba + 2HCl → BaCl2 + H2

and you placed a 2 in front of the HCL

The density of the object can be calculated using the formula Density = Mass / Volume. With the given mass of 40g and an volume of 31 cm³, the calculated density is 1.29 g/cm³.

The essential formula to remember here is: Density = Mass / Volume (represented as p=m/v), which you can use to calculate the density of any object if you know its mass and volume.

In this scenario, the mass (m) is given as 40g and the volume (V) as 31 cm³. Substituting m and V into the density formula gives:

Density = 40g / 31 cm³ = 1.29 g/cm³

Therefore, the density of the object in question is 1.29 g/cm³.

https://brainly.com/question/30804235

#SPJ2

To calculate the volume of a piece of iron, we need to use the formula: Volume = Mass / Density. First, convert the density from g/cm^3 to kg/dL, then substitute the given mass and density into the formula. By converting the final volume from cm^3 to dL, the answer will be in the desired units.

To calculate the volume of a piece of iron with a given mass, we need to use the formula:

Volume = Mass / Density

First, we need to convert the density from g/cm3 to kg/dL. There are 10 g in 1 dL and 1,000 cm3 in 1 L, so:

Density = 7.86 g/cm3 x (1 dL/10 g) x (1 L/1,000 cm3)

Now, we can substitute the given mass of 3.52 kg and the converted density into the formula to find the volume:

Volume = 3.52 kg / (converted density)

After calculating the value, we can convert the final volume from cm3 to dL by recognizing that 1 cm3 is equal to 0.1 dL.

https://brainly.com/question/13855206

#SPJ2

I would say D.  

A is incorrect by simple reasoning.

B is also incorrect. A hypothesis is made before evidence supports it, therefore, it doesn't matter if all evidence supports it,  as it shows an guess. It sometimes can also lead to more experimentation even if it's not true for the current experiment.

C is also incorrect. An untestable hypothesis isn't useful as you cannot test anything relating to it, and it cannot be proven or disproven.

Hope this helps!

The statement that is true regarding scientific hypotheses B. A testable hypothesis is valuable, even if evidence shows that it is false.

In the scientific method, a hypothesis is a proposed explanation for a phenomenon or observed behavior. A testable hypothesis is one that can be tested through experiments or observations. Even if the evidence shows that the hypothesis is false, it is still valuable because it helps researchers eliminate incorrect explanations and refine their understanding of the topic.

For example, let's say a researcher hypothesizes that a new drug will cure a particular disease. They conduct experiments and analyze the data, only to find that the drug does not have the desired effect. The hypothesis may be proven false, but the research process can still provide valuable insights and pave the way for new hypotheses or solutions.

https://brainly.com/question/2584189

#SPJ6

A pure substance contains its own contents only. The pure substance among the given options is pumpkin pie because it contains no other contents.

What is a pure substance?

A pure substance contains only its own contains and not any other things are added to it. Water Itself is pure despite the quality of water. But when we add salt or sugar to it it cannot be classified as a pure substance.

Salt is a naturally made chemical compound but it might contains some impurities and the traces other minerals in it since it is collected from the sea.

Iced tea is not classified as pure because, it contains ice, tea powder, sugar and water. Thus, it is a mixture of different substances. Pumpkin pie is naturally made fruit  contains its pulp and seed only not any added things are there.

Hence, pumpkin pie can be classified as a pure substance and option C is correct.

To find more about pure substances, refer the link below:

https://brainly.com/question/24415838

#SPJ5

Construct a hypothesis  part of the scientific method is he missing from this scientific investigation. Thus option B is correct.

Scientific investigation is a continuous process involving different steps to find out the answer to a real question by using method and experimental data.

The basic steps include to make observation from different sources, to develop, experiment and improve a hypothesis and formulate the explanation based on an observed phenomenon.

The different steps of Scientific Investigation are making Observation in scientific investigation is the first step to observe the process involve in the step of inspection, conducting the investigations.

Asking Questions another step used based on observation to make sure that every detail is known and a query can be solved quickly, Formulation of a Hypothesis involves explanation of  the query which is most significant part of the scientific investigation.

conclusion leads to  drawn out of the information which should be proper scientific or a mathematical statement followed by Communication of the information from the investigation

For more details regarding scientific investigation , here

brainly.com/question/12877466

#SPJ2

Answer:

Suppose you were to make a ring from a single strand of gold atoms. Then you have to take the following steps;

Let us assume that the ring is a size 7 ring, which has a circumference of 54.3 millimeters. Converting this to centimeters, the circumference of the ring is:

54.3 mm = 5.43 cm

Now, we determine the number of gold atoms that will be present in this:

5.43 / 1 x 10⁻⁹

There will be 5.43 x 10⁹ atoms

We now determine the number of moles this is by:

one mole = 6.02 x 10²³ atoms

Moles = 5.43 x 10⁹ / 6.02 x 10²³ 

Moles = 9.01 x 10⁻¹⁵ moles

The molar mass of gold is 197 g/mol

The mass is 9.01 x 10⁻¹⁵  * 197

The mass of the strand is 1.76 x 10⁻¹² grams

A balanced chemical equation should have same number of same kind of atoms with the same charge on both the sides of reaction.

In other words, a chemical reaction where the number of atoms for each element in the reaction and the total charge on them are the same, for both the reactants and the products is called as a balanced chemical equation.

Also, the mass and the charge should balanced on both sides of the reaction.

Final answer:

The best description of a balanced chemical equation is that it has the same number of the same kind of atoms on both sides, reflecting the conservation of matter. Balancing involves adjusting coefficients to achieve this equality.

Explanation:

The statement that best describes a balanced chemical equation is 'D. There are the same number of the same kind of atoms on either side of the reaction.' Balancing a chemical equation ensures compliance with the law of conservation of matter, indicating that atoms are neither created nor destroyed in a chemical reaction.

To balance a chemical equation, we insert coefficients in front of the appropriate reactants or products until there is the same number and type of atoms on both sides of the arrow. For instance, if a reaction produces CO₂ and H₂O, we would count the oxygen atoms in both molecules to ensure they match the total number of oxygen atoms in the reactants.

Therefore, balancing equations is a fundamental process in chemistry that illustrates the conservation of atoms during chemical reactions and ensures that the numbers of each type of atom are equal on both sides of the equation.