All categories

3 years ago

Ill give brainlists

1 answer:

3 0

I think B would be the right answer, because knowing the feedback of results of the insecticide would give you more knowledge on which one would be less dangerous for animals and children.

You might be interested in

In a chemical reaction, which are the most likely products of these reactants 4Fe+302

Cerrena [4.2K]

2Fe2O3, reason is when we add 4Fe + 3O2, we get the same answer, but in a different form.

8 0

3 years ago

_______ is the process in which light energy is transformed into food energy. A.life B.photosynthesis C.abiotic D.biotic

kolezko [41]

Answer:

B) Photosynthesis is the process in which light energy is transformed into food energy.

4 0

2 years ago

Read 2 more answers

Classify each of the following as a homogeneous or heterogeneous substance.

Mnenie [13.5K]

Answer:

a). iron ore - is a heterogeneous substance.

b). quartz - is a homogeneous substance.

c). granite - is a heterogeneous substance.

d). energy drink - is a heterogeneous substance.

e). oil-and-vinegar salad dressing - is a heterogeneous substance.

f). salt - is a homogeneous substance.

g). rainwater - is a heterogeneous substance.

h). nitrogen - is a homogeneous substance.

Explanation:

a). iron ore - is a heterogeneous substance as iron core contains iron and other impurities

b). quartz - is a homogeneous substance as it is only made up of carbon

c). granite - is a heterogeneous substance as it is made up of multiple minerals.

d). energy drink - is a heterogeneous substance as it contains various substances mixed in it

e). oil-and-vinegar salad dressing - is a heterogeneous substance as oil and vinegar itself are different compounds

f). salt - is a homogeneous substance as it only contains one type of molecule

g). rainwater - is a heterogeneous substance as it contains water and other minerals

h). nitrogen - is a homogeneous substance as it is only made of one type of molecule.

5 0

1 year ago

What is the mass of 4.99×1021 platinum atoms?

charle [14.2K]

Answer:

$\boxed {\boxed {\sf 1.62 \ g \ Pt}}$

Explanation:

We are asked to find the mass of a number of platinum (Pt) atoms.

<h3>1. Convert Atoms to Moles </h3>

First, we convert atoms to moles using Avogadro's Number or 6.022 × 10²³. This is the number of particles (atoms, molecules, formula units, etc.) in 1 mole of a substance. In this case, the particles are platinum atoms.

We will convert using dimensional analysis so we set up a ratio using the information we know (6.022 × 10²³ platinum atoms in 1 mole of platinum).

$\frac {6.022 \times 10^{23} \ atoms \ Pt}{ 1 \ mol \ Pt}$

We are converting 4.99 ×10²¹ atoms of Pt to moles of Pt, so we multiply by this value.

$4.99 \times 10^{21} \ atoms \ Pt *\frac {6.022 \times 10^{23} \ atoms \ Pt}{ 1 \ mol \ Pt}$

Flip the ratio so the units of atoms of platinum cancel.

$4.99 \times 10^{21} \ atoms \ Pt *\frac { 1 \ mol \ Pt}{6.022 \times 10^{23} \ atoms \ Pt}$

$4.99 \times 10^{21} *\frac { 1 \ mol \ Pt}{6.022 \times 10^{23}}$

$\frac { 4.99 \times 10^{21}}{6.022 \times 10^{23}} \ mol \ Pt$

Divide.

$0.008286283627 \ mol \ Pt$

<h3>2. Convert Moles to Grams </h3>

Next, we convert moles to grams using the molar mass. This is the mass of 1 mole of a substance. This is found on the Periodic Table because it is equivalent to the atomic mass, but the units are grams per mole instead of atomic mass units. Look up platinum's molar mass.

Pt: 195.08 g/mol

Set up another ratio using this new information (195.08 grams of Pt in 1 mole of Pt).

$\frac {195.08 \ g \ Pt}{ 1 \ mol \ Pt}$

Multiply by the number of moles we just calculated.

$0.008286283627 \ mol \ Pt*\frac {195.08 \ g \ Pt}{ 1 \ mol \ Pt}$

The units of moles of platinum cancel.

$0.008286283627*\frac {195.08 \ g \ Pt}{ 1 }$

$0.008286283627* {195.08 \ g \ Pt}$

$1.61648821\ g \ Pt$

<h3>3. Round</h3>

The original measurement of atoms ( 4.99 ×10²¹ ) has 3 significant figures, so our answer must have the same. For the number we found, that is the hundredth place. The 6 in the thousandth place tells us to round the 1 up to a 2.

$1.62 \ g \ Pt$

There are approximately <u>1.62 grams of platinum</u> in 4.99 ×10²¹ atoms of platinum.

8 0

3 years ago

What type of lens is shown -covex lens<br> -this isnt a lens<br> concave lens

sleet_krkn [62]

$\mathfrak{\huge{\orange{\underline{\underline{AnSwEr:-}}}}}$

Actually Welcome to the Concept of the Lens and Ray Optics.

We must understand the Concept that,

1.) When a beam of parallel light pass through a Convex lens, all the rays get deviated and converges to a special point at the axis that is a Focus.

2.) When a beam of light passes through the Concave lens,the light beams diverge from one another forming a virtual focus in the primary side of lens,

Hence the above given diagram beam rays are diverging, it is a CONCAVE LENS

answer is C.) Concave lens

6 0

2 years ago