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3 years ago

What does "cells come from other cells" mean?

Chemistry

1 answer:

Nady [450]3 years ago

4 0

Answer:

B. Cells are only created from other cells

Explanation:

Cells make a copy of themselves and then theres another cell just like the last, kinda like copy and paste

You might be interested in

Round the following number to four figures: 45.4673

zhenek [66]

This says four figures. The 4 figures you should use are 4546 with a peek at 7 to see what effect it will have on the 4 main figures.

45.467 rounds to 45.47

You round the 4th figure up one. You are not concerned about the decimal places in this question.

7 0

3 years ago

Read 2 more answers

Which of these would most likely be one of the final steps when performing a strong acid-base titration? Prepare the burette. Re

DanielleElmas [232]

Answer is: Prepare to measure pH change.

For example for strong acid-base titration, sodium hydoxide and hydrochloric can be used.

Balanced chemical reaction: HCl + NaOH → NaCl + H₂O.

In this reaction pH of equivalence point will be always 7.

Equivalence point is the point which there is stoichiometrically equivalent amounts of acid and base.

Chemist can draw pH curve (graph showing the change in pH of a solution, which is being titrated) for titration and determine equivalence point.

Near equivalence point indicator should change color, so we must pick indicator who change color near pH of equivalence point.

8 0

3 years ago

Read 2 more answers

A 237g sample of molybdnum metal is heated to 100.1 0C and then dropped into an insulated cup containing 244 g of water at 10.0

miv72 [106K]

Answer:

The specific heat of molybdenum is 0.254 joules per gram-Celsius.

Explanation:

We consider the system formed by the molybdenum metal and water as our system, a control mass inside an insulated cup, that is, a container that avoids any energy and mass interactions between system and surroundings.

From statement we notice that metal is cooled down whereas water is heated. According to the First Law of Thermodynamics, we know that:

$Q_{metal} - Q_{water} = 0$

$Q_{metal} = Q_{water}$

Where:

$Q_{water}$ - Heat received by water, measured in joules.

$Q_{metal}$ - Heat released by metal, measured in joules.

Now we expand this identity by definition of sensible heat:

$m_{metal}\cdot c_{metal}\cdot (T_{m,o}-T) = m_{water}\cdot c_{water}\cdot (T-T_{w,o})$

The specific heat of the metal is cleared within equation above:

$c_{metal} = \frac{m_{water}\cdot c_{water}\cdot (T-T_{w,o})}{m_{metal}\cdot (T_{m,o}-T)}$

If we know that $m_{water} = 0.237\,kg$ , $m_{metal} = 0.244\,kg$ , $c_{water} = 4186\,\frac{J}{kg\cdot ^{\circ}C}$ , $T_{w,o} = 10\,^{\circ}C$ , $T_{m,o} = 100.10\,^{\circ}C$ and $T = 15.30\,^{\circ}C$ , the specific heat of molybdenum is:

$c_{metal} = \frac{(0.237\,kg)\cdot \left(4186\,\frac{J}{kg\cdot ^{\circ}C} \right)\cdot (15.30\,^{\circ}C-10\,^{\circ}C)}{(0.244\,kg)\cdot (100.10\,^{\circ}C-15.30\,^{\circ}C)}$

$c_{metal} = 254.119\,\frac{J}{kg\cdot ^{\circ}C}$

The specific heat of molybdenum is 0.254 joules per gram-Celsius.

5 0

3 years ago

How many grams of sodium oxide can be synthesized from 17.4 g of sodium? assume that more than enough oxygen is present. the bal

Tatiana [17]

Equation is as follow,

 4 Na (s) + O₂ (g) → 2Na₂O (s)

According to equation,

91.92 g (4 moles) of Na produces = 123.92 g (2 moles) of Na₂O
So,
17.4 g of Na will produce = X g of Na₂O

Solving for X,
X = (17.4 g × 123.92 g) ÷ 91.92 g

X = 23.45 g of Na₂O

7 0

3 years ago

Calculate the molarity of an HCl solution if 23.88 mL of it reacts with 6.5287 grams of sodium carbonate (106 g/mol) according t

Ivanshal [37]

Answer:

5.158 mol/L

Explanation:

To find the molarity, you need to use the formula:

Molarity (M) = moles / volume (L)

You have been grams sodium carbonate. You need to (1) convert grams Na₂CO₃ to moles (via molar mass), then (2) convert moles Na₂CO₃ to moles HCl (via mole-to-mole ratio from equation), then (3) convert mL to L (by dividing by 1,000), and then (4) use the molarity equation.

Steps 1 - 2:

2 HCl + 1 Na₂CO₃ ----> 2 NaCl + H₂O + CO₂

6.5287 g Na₂CO₃ 1 mole 2 moles HCl
-------------------------- x ------------- x ------------------------- = 0.12318 mole HCl
106 g 1 mole Na₂CO₃

Step 3:

23.88 mL / 1,000 = 0.02388 L

Step 4:

Molarity = moles / volume

Molarity = 0.12318 mole / 0.02388 L

Molarity = 5.158 mole/L

**mole/L is equal to M**

7 0

2 years ago