I am something that is alive or was once alive.

What scientists do that is the basis for their investigation

Vlada [557]

They utilize and make use of the scientific method in order to have clear basis and evidence for their investigations. Research method is always used to answer every scientific inquiry and in gaining evidential data or knowledge. The scientific method has the following process or at least undergoes the process of
1. Observation
2. Hypothesis 
3. Experimentation 
4. Interpretation of data 
5. Evaluating the data 
6. Passing and recording the data 

These steps are crucial and the empirical data that these scientists obtain are very important to keep that is why research paper, thesis and dissertations exists.

5 0

4 years ago

A student dissolves 6.2g of aniline c6h5nh2 in 350.ml of a solvent with a density of 1.04/gml . the student notices that the vol

Troyanec [42]

Answer : The correct answer for molarity = 0.19 $\frac{mol}{L}$ and Molality = 0.18 $\frac{mol}{Kg}$ .

Given : Mass of aniline = 6.2 g

Volume of solvent = 350 mL Density of solvent = 1.04 g/mL

1) Molarity : It is defined as number of moles of solute present in Litre of solution . It is expressed as :

$Molarity(M) = \frac{moles of solute(mole)}{volume of solution (L)}$ \

Molairty can be found in following steps :

Step 1 : To calculate mole :

Mole of solute can be calculate using mole formula :

$Mole of solute = \frac{given mass of solute (g)}{molar mass of solute\frac{g}{1 mol}}$

Molar mass of aniline (C₆H₅NH₂) = 93.13 $\frac{g}{1 mol}$

Mass of aniline = 6.2 g

Plugging values in mole formula :

$Mole = \frac{6.2 g}{93.13 \frac{g}{1 mol}}$

Mole = 0.0665 mol

Step 2 : To find volume of solution

Volume of solution = volume of solute + volume of solution

Since addition of aniline does not change final volume , so volume of solvent = volume of solution. Since volume is given in mL , so it need to be converted to L .

1 L = 1000mL

$Volume of solution = \frac{350 mL}{1000mL} * 1 L$

Volume of solution = 0.350 L

Step 3: Plug value of mole and volume in molarity formula :

$Molarity = \frac{0.0665 mol}{0.350 L }$

Molarity = 0.19 M or 0.19 $\frac{mol}{L}$

------------------------------------------------------------------------------------------

2) Molality : It is defined as mole of solute present in Kilogram of solvent . It can be expressed as :

$Molality (m) = \frac{mole of solute (mol)}{Kilogram of solvent (Kg)}$

Following are the steps to calculate molality :

Step 1: To find mole of Solute :

Mole of solute can be found out using mole formula . It is same as done for molarity .

Mole = 0.0665 mol

Step 2 : To find kilogram of solvent :

Mass of solvent can be calculated using density formula as :

$Density \frac{g}{mL} = \frac{mass (g) }{volume (mL)}$

Plugging value in density formula :

$1.04 \frac{g}{mL} = \frac{ mass }{350 mL}$

Multiplying both side by 350 mL

$1.04 \frac{g}{mL} * 350 mL = \frac{x}{350 mL } * 350 mL$

Mass of solvent = 364 g

Since mass is in g, it need to be converted to Kg . ( 1 Kg = 1000 g )

$Mass of solvent = \frac{364 g}{1000g} * 1 Kg$

Mass of solvent = 0.364 Kg

Step 3: Plug values of mole and Kg in molality formula :

$Molality = \frac{0.0665 mol}{0.364 Kg}$

Molality = 0.18 m or 0.18 $\frac{mol}{Kg}$

3 0

3 years ago

How much ice at a temperature of -17.5 ∘C must be dropped into the water so that the final temperature of the system will be 31.

Tanya [424]

Answer:

An insulated beaker with negligible mass contains liquid water with a mass of 0.205kg and a temperature of 79.9 °C How much ice at a temperature of −17.5 °C must be dropped into the water so that the final temperature of the system will be 31.0 °C? Take the specific heat for liquid water to be 4190J/Kg.K, the specific heat for ice to be 2100J/Kg.K, and the heat of fusion for water to be 334000J/kg.

The answer to the above question is

Therefore 0.1133 kg ice at a temperature of -17.5 ∘C must be dropped into the water so that the final temperature of the system will be 31.0 °C

Explanation:

To solve this we proceed by finding the heat reaquired to raise the temperature of the water to 31.0 C from 79.9 C then we use tht to calculate for the mass of ice as follows

ΔH = m×c×ΔT

= 0.205×4190×(79.9 -31.0) = 42002.655 J

Therefore fore the ice, we have

Total heat = mi×L + mi×ci×ΔTi = mi×334000 + mi × 2100 × (0 -−17.5) = 42002.655 J

370750×mi = 42002.655 J

or mi = 0.1133 kg

Therefore 0.1133 kg ice at a temperature of -17.5 ∘C must be dropped into the water so that the final temperature of the system will be 31.0 °C

5 0

3 years ago

The application of knowledge to solve practical problems is known as what?

GenaCL600 [577]

Is known as “Technology”

7 0

3 years ago

Compare the size of I, I+ and I-

elixir [45]

umm explanation pls so i answee

7 0

3 years ago

Read 2 more answers