please help me with these questions, im not understanding :(

Answer:

May be the instrument is incorrect or may be error in it.

Explanation:

The copper have not been detected by this test because the test may be not for the detection of copper, may be it is used for identification of another minerals. If there is copper in the lake sample but can't be detected in the test so it means that the instrument which is used for detection is not the right one  or having error in that instrument. Every mineral has a specific type of instrument that detect its presence, if we use incorrect instrument for the mineral then we can't detect the presence of that specific mineral.

Answer:

Protons / H+ ions

Explanation:

The acids are compounds with a pH range between 1-7, while the base has a pH range of 7-14. Acids produce hydrogen ions or protons in the solution.

The pH can be defined as the hydrogen ion concentration in the solution. The higher the proton concentration in the solution, the lower will be the pH.

The pH of 7 has an equal number of hydrogen and hydroxide ions contributing to the neutral pH. The alkaline pH is contributed by the hydroxide ion concentration.

The acids fall at the lower pH range with a high hydrogen ion concentration. Thus, acids produce hydrogen ions or protons in the aqueous solution.

Learn more about acids, here:

https://brainly.com/question/1515003

Explanation:

Na2CO3+Ca(No3)2---> CaCO3+2NaNo3

Answer:

The right response is "6 A". A further explanation is given below.

Explanation:

The given values are:

Resistance,

R = 6 ohms

Voltage,

V = 36 volts

As we know,

⇒  [tex]V=IR[/tex]

then,

⇒  [tex]I=\frac{V}{R}[/tex]

On substituting the values, we get

⇒     [tex]=\frac{36}{6}[/tex]

⇒     [tex]=6 \ A[/tex]

Answer:

Indo-Australian

Explanation:

Indo-Australian does not appear in both hemispheres.

Answer:

I can clarify, its into Australian

Answer:

To show what they know!

Explanation:

If you're not showing how you did your experiment thoroughly, then nobody will understand what you did! For instance, if you spent 2 weeks studying really hard about how music affects different kinds of animals, and only put down that music affects animals and no showing your work. Then no one will know how much effort and work you put into it! If you put all the minor details into the presentation, then more than likely everyone will know where your coming from!

Hope this helps! Plz mark as brainliest!

Answer:

A

Explanation: 11/22

You divide by the mass of the solution.

Percent by mass is the mass of the solute divided by the mass of the solution, multiplied by 100.

Example:

You dissolve a 4.00 g sugar cube in 350 mL of tea at 80 °C. The density of water at 80 °C is 0.975 g/mL. What is the percent by mass of sugar in the solution?

Solution

Step 1 — Determine mass of the solute.

The solute is the sugar cube. Mass of solute = 4.00 g.

Step 2 — Determine mass of solvent.

The solvent is the 80 °C water. Use the density of the water to find the mass.

mass of solvent = 350 mL ×

0.975

g

1

mL

= 341 g

Step 3— Determine the total mass of the solution

mass of solution = mass of solute + mass of solvent = 4.00 g + 341 g = 345 g

Step 4 — Determine percent composition by mass of the sugar solution.

% by mass =

mass of solute

mass of solution

× 100 % =

4.00

g

345

g

× 100 % = 1.159 %

The percent composition by mass of the sugar solution is 1.159 %.

Answer:

same I was looking for a question like this I was asking question and someone kept commenting this bitly thing i dont kno I though it was just weird and frustrating lol

Answer:

10.Semi-Solid

11.Liquid

12.Solid

13:Semi-Solid

Answer:

Gaseous nitrogen has unique chemical and physical properties that make it suitable for use in food processing. Nitrogen is inert which means it will not react with prepared food materials, which can alter their aromas or flavors. Also, gaseous nitrogen will effectively displace oxygen minimizing oxidation and the growth of microorganisms that cause foods to lose their freshness and deteriorate faster.

Explanation:

Source: https://www.generon.com/using-nitrogen-gas-in-food-packaging/

"Because it deflects oxygen, nitrogen is just a common gas for food packing." Because oxygen will carry moisture, this is critical. Bacteria use oxygen to grow and survive on organic matter. Bacteria find it much harder to develop while as much oxygen as possible is removed.

Food packaging is the process of packaging food. A package provides security, resistance to manipulation, and particular physical, chemical, and even biological requirements.  Food packaging may include a nutrition label and other information about the product being sold.

Bacteria are commonly found, mostly free-living organisms with  one biological cell. They belong to the prokaryotic organisms category. Bacteria, which have been typically a few micrometers long, were one of the first living species to originate on Earth and may be found in practically every ecosystem.

To know more about food packing click here.

https://brainly.com/question/15884787

#SPJ2

Answer:

decreases

Explanation:

Gravirational force is directly proportional to the mass and inversely proportional to the distance.(Newton's law of gravitation)

Answer:

The answer to this question is HCl(aq) + H2O(l) = H3O+(aq) + Cl-(aq). HCl is considered a strong acid meaning it is 100% ionized in solution. The equilibrium constant is therefore very large.

Answer:

no it's is false because an electron have negative charges and it is not inside the atom and it is found out side the nucleus

Answer:

a. i. 5.092 × 10²⁰ Hz ii. 588.98554 nm ii. 10667809.11 rad/m

b. i. 5.087 × 10²⁰ Hz ii. 589.58286 nm iii. 10657001.3 rad/m

Explanation:

refractive index, n = λ/λ'  where λ = wavelength in vacuum = and λ' = wavelength in air

a. For λ = 589.15788 nm,

i. Frequency,

f = c/λ where c = speed of light in vacuum = 3 × 10⁸ m/s and λ = 589.15788 nm = 589.15788 × 10⁻⁹ m

So, f = 3 × 10⁸ m/s ÷ 589.15788 × 10⁻⁹ m

= 0.005092 × 10¹⁷ /s

= 5.092 × 10²⁰ /s

= 5.092 × 10²⁰ Hz

ii. Wavelength,

Since n = λ/λ'  where λ = wavelength in vacuum = and λ' = wavelength in air

and n = 1.0002926

λ' = λ/n

= 589.15788 nm/1.0002926

= 588.98554 nm

k = 2π/λ'

= 2π/588.98554 nm

= 0.01066780911 rad/nm

= 0.01066780911 rad/nm × 10⁹ nm/1m

= 10667809.11 rad/m

b. For λ = 589.755 37 nm.,

i. Frequency,

f = c/λ where c = speed of light in vacuum = 3 × 10⁸ m/s and λ = 589.755 37 nm. = 589.755 37 × 10⁻⁹ m

So, f = 3 × 10⁸ m/s ÷ 589.755 37 × 10⁻⁹ m

= 0.005087 × 10¹⁷ /s

= 5.087 × 10²⁰ /s

= 5.087 × 10²⁰ Hz

ii. Wavelength,

Since n = λ/λ'  where λ = wavelength in vacuum = and λ' = wavelength in air

and n = 1.0002926

λ' = λ/n

= 589.755 37 nm./1.0002926

= 589.58286 nm

k = 2π/λ'

= 2π/589.58286 nm

= 0.0106570013 rad/nm

= 0.0106570013  rad/nm × 10⁹ nm/1m

= 10657001.3 rad/m

Answer:

Option B

Explanation:

The atmospheric pressure in West Chester, Pennsylvania is lower than the pressure on any summer day in Breckenridge, Colorado

Colorado is 1.6 kilometers above sea level while Pennsylvania is 0.33 kilometers above sea level.

The higher a place is above sea level, the higher is the air pressure.

Hence, option B is correct

Answer:

1.3244 x 10⁴⁹ atoms of zinc

Explanation:

2.20 x 10²⁵ moles

To convert from moles to atoms, we multiply by Avogadro's Number, 6.02 x 10²³

2.20 x 10²⁵ • 6.02 x 10²³

= 1.3244 x 10⁴⁹ atoms of zinc

Hope this helps!

Answer:

1. (NH₄)₂S(s) -----> NH₄+(aq) + S²-(aq)

2. Al³+ (aq) + PO₄³+ (aq) ----> AlPO₄ (s)

Explanation:

The dissociation of ammonium sulphide, (NH₄)₂S when dissolved in water is given in the equation below:

(NH₄)₂S(s) -----> NH₄+(aq) + S²-(aq)

However very little S²- ions are present in solution due to the very basic nature of the S²- ion (Kb = 1 x 105).

The ammonium ion being a better proton donor than water, donates a proton to sulphide ion to form hydrosulphide ion which exists in equilibrium with aqueous ammonia.

S²- (aq) + NH₄+ (aq) ⇌ SH- (aq) + NH₃ (aq)

Aqueous solutions of ammonium sulfide are smelly due to the release of hydrogen sulfide and ammonia, hence, their use in making stink bombs.

2. The reaction between aluminium nitrate and sodium phosphatein aqueous solution is a double decomposition reaction whish results in the precipitation of insoluble aluminium phosphate. The equation of the reaction is given below :

Al(NO₃)₃ (aq) + Na₃PO₄ (aq) ----> AlPO₄ (s) + 3 NaNO₃ (aq)

The net ionic equation is given below:

Al³+ (aq) + PO₄³+ (aq) ----> AlPO₄ (s)

Answer:

NaBr

Explanation:

Answer:

um...id.k how to do chemistry...help please?

Explanation:

NaBr

Answer:

20 km/h

Explanation:

Speed = distance ÷ time

Speed = 10 ÷ 0.5 hours

Speed = 20 km/hr

Answer: 110

Explanation:

Answer:

Molecular mass is a number equal to the sum of the atomic masses of the atoms in a molecule.

Explanation:

The molecular mass gives the mass of a molecule relative to that of the 12 C atom, which is taken to have a mass of 12. Hence why Molecular mass is a number equal to the sum of the atomic masses of the atoms in a molecule.

Answer:

a, they are the building blocks of proteins.

Explanation:

hope this helps!

~mina

Answer:

A. They are the building blocks of proteins.

(Photo for proof at the bottom.)

Explanation:

Glycine, leucine, and lysine are all amino acids. There are 20 different kinds of amino acids, including the 3 mentioned here. Different amino acids bond together to form different structures, depending on how many there are. Generally, 50 or more amino acids bonded together makes a protein. But there are some exceptions. Amino acids (including glycine, leucine, and lysine) are the building blocks of proteins.

Here's a photo of Edge incase you're doubtful.

Please click the heart if this helped.