1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
vitfil [10]
3 years ago
14

How many protons does technetium have?

Chemistry
1 answer:
kari74 [83]3 years ago
5 0
Technetium has 43 protons.
You might be interested in
Calculate: (a) the weight (in lbf) of a 30.0 lbm object. (b) the mass in kg of an object that weighs 44N. (c) the weight in dyne
belka [17]

Answer:

a) 965,1 lbf

b) 4,5 kg

c) 1,33 * 10^6 dynes

Explanation:

Mass of an object refers to the amount of mattter it cotains, it can be expressed it gr, kg, lbm, ton, etc.

Weight of an object refers to a force, and is the measurement of the pull of gravitiy on an object. It may be definide as the mass times the acceleration of gravity.

                                        w=mg

In Planet Earth, the nominal "average" value for gravity is 9,8 m/s² (in the International  System) or 32,17 ft/s² (in the FPS system).

To solve this problem we'll use the following conversion factors:

1 lbf = 1 lbm*ft/s²

1 N = 1 kg*m/s²

1 dyne = 1 gr*cm/s²   and 1 N =10^5 dynes

1 ton = 907,18 kg

1 k = 1000 gr

a) m = 30 lbm

w = 30 lbm * 32,17 ft/s^{2} = 965, 1 \frac{lmb*ft}{s^{2} } = 965,1 lbf

b) w = 44 N

First, we clear m of the weight equation and then we replace our data.

m = \frac{w}{g} = \frac{44 N}{9,8 \frac{m}{{s}^{2}} } = 4,5 kg

c) m = 15 ton

m=15 ton * \frac{907,18 kg}{1 ton} = 13607,7 kg \\ w = mg = 13607,7 kg * 9,8 m/s2 = 133355,5 N * \frac{10^{5} dynes }{1 N} = 1,33 * 10^{6}dynes

4 0
4 years ago
What are the limitations of the Klmn electronic configuration style of writing
Salsk061 [2.6K]

In the KLMN electronic configuration style of writing K denotes the first shell which can hold up to two electrons, L denotes the second shell which can hold up to eight (2 + 6) or 8 electrons, M denotes the third shell which can hold up to eight (2 + 6 + 10) or 18 electrons etc.

The KLMN style of writing  only indicates the number of electrons in each principal quantum number, however the spdf electronic configuration style of writing subdivides each shell into its subshells.

For instance the 3rd principal quantum number has s,p and d subshells, wherein s, p and d orbitals can have a maximum of 2, 6 and 10 electrons respectively.


5 0
3 years ago
Find the density of a substance that has a mass of 75 g and a volume of 35 mL. Don't forget your units!
Andrew [12]

Answer:

The density of a substance that has a mass of 75 g and a volume of 35 mL is 2.14 \frac{g}{mL}

Explanation:

Density is a characteristic property of a substance that relates to the amount of mass it has per unit volume. In other words, density is the property that matter, whether solid, liquid or gas, has to compress into a given space (it measures the amount of mass in a given volume of a substance). It is calculated as the quotient between the mass of a body and the volume it occupies:

density=\frac{mass}{volume}

In this case, you know:

  • mass= 75 g
  • volume= 35 mL

Replacing:

density=\frac{75 g}{35 mL}

Solving:

density=2.14\frac{g}{mL}

<u><em>The density of a substance that has a mass of 75 g and a volume of 35 mL is 2.14 </em></u>\frac{g}{mL}<u><em></em></u>

5 0
3 years ago
When fossil fuels are burned, they release energy stored years ago. true or false
Mariulka [41]

Answer:true

Explanation:

5 0
3 years ago
6. What happens when a piece of sodium is dropped into water?​
Sloan [31]
Sodium’s combination with water creates a colourless result of sodium hydroxide (NaOH) and hydrogen gas (H2). ... The reaction is exothermic. During the reaction, the sodium metal become very hot, to the point where it can catch fire and burns with a characteristic orange colour.
3 0
3 years ago
Other questions:
  • What chemical compound provides energy for cells?​
    8·2 answers
  • Which way will heat flow when ice and water are combined in a glass?
    12·2 answers
  • What is the relationship between mass and solubility
    11·2 answers
  • Compare a photon and quantum. How are they alike? How are they different?
    15·1 answer
  • How many atoms of each element are contained in a single formula unit of Iron III formate, Fe(CH02)3 x H20? What percentrage by
    13·1 answer
  • One dose of a liquid medication is 2.5 tablespoons. If a patient takes a dose of this medication four times a day for a week, ho
    7·1 answer
  • Indicate how many significant figures in the following number 1.080
    7·1 answer
  • The diameter of a red blood cell is about 3 × 10−4 in. What is its diameter in centimeters?
    5·2 answers
  • A special layer of dermal cells are found on the top side of leaves. What level of organization would it belong to
    5·1 answer
  • 5Fe2 2Mn2 8H2O2MnO4- 5Fe 16H In the above reaction, the oxidation state of iron changes from to . How many electrons are transfe
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!