All categories

3 years ago

Helpppppppppppppppppppppppppppppppppp

Chemistry

1 answer:

dimulka [17.4K]3 years ago

5 0

These could all go either way, hardness and other special properties are what I'm guessing would be the most accurate in determining the kind of material.
luster, cleavage, streak, and color can all be affected by other factors. but I guess cleavage would also be accurate. so I guess hardness special properties and cleavage would be the most reliable.

You might be interested in

3- Fully folded proteins typically have polar side chains on their surfaces, where electrostatic attractions and hydrogen bonds

Elden [556K]

Answer:

Option C= A hydrogen bond formed between a polar side chain and a hydrophobic side chain.

Explanation:

All three given options a, b and d have common mechanism to accommodate the polar amino acid.

A= A hydrogen bond forms between two polar side chains.

B= A hydrogen bond from between a polar side chain and protein back bone.

D = hydrogen bond form between polar side chains and a buried water molecules.

All these are use to accommodate the polar amino acid.

While option C is not used. which is:

A hydrogen bond formed between a polar side chain and a hydrophobic side chain.

5 0

3 years ago

Calculate ΔH o rxn for the following: CH4(g) + Cl2(g) → CCl4(l) + HCl(g)[unbalanced] ΔH o f [CH4(g)] = −74.87 kJ/mol ΔH o f [CCl

anzhelika [568]

Answer: ΔH for the reaction is -277.4 kJ

Explanation:

The balanced chemical reaction is,

$CH_4(g)+Cl_2(g)\rightarrow CCl_4(l)+HCl(g)$

The expression for enthalpy change is,

$\Delta H=\sum [n\times \Delta H(products)]-\sum [n\times \Delta H(reactant)]$

$\Delta H=[(n_{CCl_4}\times \Delta H_{CCl_4})+(n_{HCl}\times B.E_{HCl}) ]-[(n_{CH_4}\times \Delta H_{CH_4})+n_{Cl_2}\times \Delta H_{Cl_2}]$

where,

n = number of moles

Now put all the given values in this expression, we get

$\Delta H=[(1\times -139)+(1\times -92.31) ]-[(1\times -74.87)+(1\times 121.0]$

$\Delta H=-277.4kJ$

Therefore, the enthalpy change for this reaction is, -277.4 kJ

4 0

3 years ago

Is a strong acid a. NaC₂H₃O₂ b. HC₂H₃O₂ c. KCl d. NH₃ e. HCl

sammy [17]

E. HCI

Source:
The Internet

7 0

2 years ago

1. Two boys balanced steady in a sea-saw game

anygoal [31]

Mutual

They are balanced steadily which means they’re at the same point

4 0

2 years ago

Read 2 more answers

THE CONSTANT MOVING OF AND HELP THE TEMPERATURES AROUND THE EARTH REMAIN ABOUT THE SAME AVERAGE

nika2105 [10]

New analysis through 2014 shows that temperature is once again rising at about the same pace as it did over the second half of the 20 th century. PRESS RELEASE. Using the data that were available at the time (through 2012), the last climate report from the Intergovernmental Panel on Climate Change concluded that there had been no statistically significant increase in global surface temperature

(I hope this helps you!)

8 0

3 years ago